Categories of Questions

## Array Questions Bloomberg

**Shuffle the Array Leetcode Solution** The problem Shuffle the Array Leetcode Solution provides us with an array of length 2n. Here 2n refers that the array length is even. We are then told to shuffle the array. Here shuffling does not mean that we need to randomly shuffle the array but a specific way is ...

**3Sum Leetcode Solution** Problem Statement Given an array of n integers, are there elements a, b, c in nums such that a + b + c = 0? Find all unique triplets in the array which gives the sum of zero. Notice: that the solution set must not contain duplicate triplets. Example #1 [-1,0,1,2,-1,4] ...

**Combination Sum Leetcode Solution** The problem Combination Sum Leetcode Solution provides us an array or list of integers and a target. We are told to find the combinations that can be made using these integers any number of times that add up to the given target. So more formally, we can use the given ...

**Island Perimeter Leetcode Solution** Problem Statement In this problem, we are given a grid in form of a 2-D array. grid[i][j] = 0 represents there is water at that point and grid[i][j] = 1 represents land. Grid cells are connected vertically/horizontally but not diagonally. There is exactly one island (a connected component of land ...

**Maximum Subarray Leetcode Solution** Problem Statement Given an integer array nums, find the contiguous subarray (containing at least one number) which has the largest sum and return its sum. Example nums = [-2,1,-3,4,-1,2,1,-5,4] 6 Explanation: [4,-1,2,1] has the largest sum = 6. nums = [-1] -1 Approach 1 (Divide and Conquer) In this approach ...

**Minimum Time Visiting All Points Leetcode Solution** The problem Minimum Time Visiting All Points Leetcode Solution provides us with an array or vector of points on coordinate axes. The problem after providing us with the input asks us to find the minimum time to visit all the points given in the input. When you move one unit ...

**Minimum Absolute Difference Leetcode Solution** The problem Minimum Absolute Difference Leetcode Solution provides us an unsorted array or vector containing some integers. We are required to find out all the pairs that have a difference equal to that of minimum absolute difference. The minimum absolute difference is the minimum value of absolute difference that can ...

**Find Common Characters Leetcode Solution** Problem Statement In this problem, we are given an array of strings. We need to print a list of all characters that appear in every string in the array(duplicates included). That is if a character appears 2 times in every string, but not 3 times, we need to have it ...

**Find All Numbers Disappeared in an Array Leetcode Solution** Problem Statement In this problem, we are given an array of integers. It contains elements ranging from 1 to N, where N = size of the array. However, there are some elements that have disappeared and some duplicates are present in their place. Our goal is to return an array ...

**Majority Element II Leetcode Solution** In this problem, we are given an array of integers. The goal is to find all the elements which occur more than ⌊N / 3⌋ time in the array where N = size of the array and ⌊ ⌋ is the floor operator. We need to return an array of ...

**Unique Paths Leetcode Solution** The problem Unique Paths Leetcode Solution states that you are given two integers representing the size of a grid. Using the size of the grid, the length, and breadth of the grid. We need to find the number of unique paths from the top left corner of the grid to ...

**How Many Numbers Are Smaller Than the Current Number Leetcode Solution** Problem Statement In this problem, we are given an array. For each element of this array, we have to find out the number of elements smaller than that element. i.e. for each i (0<=i<arr.length) we have to find out count of elements less than the number arr[i]. For that we ...

**Merge Sorted Arrays Leetcode Solution** In the problem “Merge Sorted Arrays”, we are given two arrays sorted in non-descending order. The first array is not fully filled and has enough space to accommodate all elements of the second array as well. We have to merge the two arrays, such that the first array contains elements ...

**Search in Rotated Sorted Array Leetcode Solution** Consider a sorted array but one index was picked and the array was rotated at that point. Now, once the array has been rotated you are required to find a particular target element and return its index. In case, the element is not present, return -1. The problem is generally ...

**Search Insert Position Leetcode Solution** In this problem, we are given a sorted array and a target integer. We have to find its Search Insert Position. If the target value is present in the array, return its index. Return the index at which the target should be inserted so as to keep the order sorted(in ...

**Kids With the Greatest Number of Candies Leetcode Solution** In the problem “Kids With the Greatest Number of Candies”, we are given an array of integers that represents the number of chocolates some children have got and some extra candies that can be distributed in any manner. Now, we need to find: Can every child have the greatest number ...

**Running Sum of 1d Array Leetcode Solution** Problem Statement In running sum of 1d array problem we have been given an array nums for which we have to return an array where for each index i in the result array arr[i] = sum( nums[0] … nums[i] ). Example nums = [1,2,3,4] [1,3,6,10] Explanation: Running sum is : ...

**Find First and Last Position of Element in Sorted Array Leetcode Solution** Problem statement In this article titled “Find First and Last Position of Element in Sorted Array Leetcode Solution,” we will discuss the solution to a leetcode problem. In the given problem we are given an array. We are also given a target element. Elements in the array are sequenced in ...

**Minimum Sum Path in a Triangle** Problem Statement The problem “Minimum Sum Path in a Triangle” states that you are given a sequence in the form of a triangle of integers. Now starting from the top row what is the minimum sum you can achieve when you reach the bottom row? Example 1 2 3 5 ...

**Length of the largest subarray with contiguous elements** The problem “Length of the largest subarray with contiguous elements” states that you are given an integer array. The problem statement asks to find out the length of the longest contiguous sub-array of which elements can be arranged in a sequence (continuous, either ascending or descending). The numbers in the ...

**Best Time to Buy and Sell Stock** Problem Statement The problem “Best Time to Buy and Sell Stock” states that you are given an array of prices of length n, where the ith element stores the price of stock on ith day. If we can make only one transaction, that is, to buy on one day and ...

**Top K Frequent Elements** Problem Statement In top K frequent elements we have given an array nums[], find the k most frequently occurring elements. Examples nums[] = {1, 1, 1, 2, 2, 3} k = 2 1 2 nums[] = {1} k = 1 1 Naive Approach for Top K Frequent Elements Build ...

**Minimum time required to rot all oranges** Problem Statement The problem “Minimum time required to rot all oranges” states that you are given a 2D array, every cell has one of the three possible values 0, 1 or 2. 0 means an empty cell. 1 means a fresh orange. 2 means a rotten orange. If a rotten ...

**Sorted Array to Balanced BST** In sorted array to balanced BST problem, we have given an array in sorted order, construct a Balanced Binary Search Tree from the sorted array. Examples Input arr[] = {1, 2, 3, 4, 5} Output Pre-order : 3 2 1 5 4 Input arr[] = {7, 11, 13, 20, 22, ...

**Subset Leetcode** In Subset Leetcode problem we have given a set of distinct integers, nums, print all subsets (the power set). Note: The solution set must not contain duplicate subsets. An array A is a subset of an array B if a can be obtained from B by deleting some (possibly, zero ...

**Word Search** Word search is something like the word-finding puzzles at some time in our life. Today I bring to the table a modified crossword. My readers must be a bit perplexed as to what I am talking about. Without wasting any more time let us get to the problem statement Can ...

**Insert Delete GetRandom** In Insert Delete GetRandom problem we need to design a data structure that supports all following operations in average O(1) time. insert(val): Inserts an item val to the set if not already present. remove(val): Removes an item val from the set if present. getRandom: Returns a random element from the current set ...

**Merge Overlapping Intervals** In merge overlapping intervals problem we have given a collection of intervals, merge and return all overlapping intervals. Example Input : [[2, 3], [3, 4], [5, 7]] Output: [[2, 4], [5, 7]] Explanation: We can merge [2, 3] and [3, 4] together to form [2, 4] Approach for finding Merge ...

**Median of Two Sorted Arrays** Given two sorted arrays A and B of size n and m respectively. Find the median of the final sorted array obtained after merging the given two arrays or in other words, we say that find median of two sorted arrays. ( Expected time complexity: O(log(n)) ) Approach 1 for ...

**Maximum Product Subarray** In the maximum product subarray problem, we have given an array of integers, find the contiguous sub-array with atleast one element which has the largest product. Example Arr=[ 0, -1, 0 ,1 ,2, -3] Maximum product = 2 Arr=[-1, -1, -1] Maximum product = -1 Arr=[0, -1, 0, -2, 0] ...

**Search an Element in Sorted Rotated Array** In search in sorted rotated array problem we have given a sorted and rotated array and an element, check if the given element is present in the array or not. Examples Input nums[] = {2, 5, 6, 0, 0, 1, 2} target = 0 Output true Input nums[] = {2, ...

**Maximum Product Subarray** Given an array of n integers, find the maximum product obtained from a contiguous subarray of the given array. Examples Input arr[] = {-2, -3, 0, -2, -40} Output 80 Input arr[] = {5, 10, 6, -2, 1} Output 300 Input arr[] = {-1, -4, -10, 0, 70} Output 70 ...

**3 Sum** In 3 Sum problem, we have given an array nums of n integers, find all the unique triplets that sum up to 0. Example Input: nums = {-1, 0, 1, 2, -1, -4} Output: {-1, 0, 1}, {-1, 2, -1} Naive Approach for 3 Sum problem The Brute force approach ...

**Find The Duplicate Number** Given an array nums containing (n + 1) elements and every element is between 1 to n. If there is only one duplicate element, find the duplicate number. Examples Input: nums = {1, 3, 4, 2, 2} Output: 2 Input: nums = {3, 1, 3, 4, 2} Output: 3 Naive ...

**Minimum Path Sum** In the minimum path sum problem, we have given “a × b” matrix consisting of non-negative numbers. Your task is to find the path from top left to right bottom which minimizes the sum consisting of all the numbers which come in a path you found. Note: You can only move ...

**Find the Duplicate Element** Given an array of integers of size n+1 where each element of the array is between 1 and n (inclusive), there is one duplicate element in the array, find the duplicate element. Brute force method – Approach 1 for Find the Duplicate Element For every ith element run a loop ...

**Trapping Rain Water** In Trapping Rain Water problem we have given N non-negative integers representing an elevation map and the width of each bar is 1. We have to find the amount of water that can be trapped in the above structure. Example Let’s understand that by an example For the above elevation ...

**Jump Game** In jump game we have given an array of non-negative integers, you are initially positioned at the first index of the array. Each element in the array represents your maximum jump length at that position. Determine if you are able to reach the last index. Example Input: arr = [2,3,1,1,4] ...

**Combination Sum** In combination sum problem we have given an array of positive integers arr[] and a sum s, find all unique combinations of elements in arr[] where the sum of those elements is equal to s. The same repeated number may be chosen from arr[] an unlimited number of times. Elements ...

**Max Area of Island** Problem Description: Given a 2D matrix, the matrix has only 0(representing water) and 1(representing land) as entries. An island in the matrix is formed by grouping all the adjacent 1’s connected 4-directionally(horizontal and vertical). Find the maximum area of the island in the matrix. Assume that all four edges of ...

**Search in Sorted Rotated Array** An element search in sorted rotated array can be found using binary search in O(logn) time. The objective of this post is to find a given element in a sorted rotated array in O(logn) time. Some example of a sorted rotated array is given. Example Input : arr[] = {7,8,9,10,1,2,3,5,6}; ...

**Unique Paths** A m x n 2D grid is given and you are standing at the topmost and leftmost cell in the grid. i.e. the cell located at (1,1). Find the number of unique paths that can be taken to reach a cell located at (m,n) from the cell located at (1,1) ...

**Maximum Subarray** In the Maximum Subarray problem we have given an integer array nums, find the contiguous sub array which has the largest sum and print the maximum sum subarray value. Example Input nums[] = {-2, 1, -3, 4, -1, 2, 1, -5, 4} Output 6 Algorithm The goal is to find ...

**Merging Intervals** In merging intervals problem we have given a set of intervals of the form [l, r], merge the overlapping intervals. Examples Input {[1, 3], [2, 6], [8, 10], [15, 18]} Output {[1, 6], [8, 10], [15, 18]} Input {[1, 4], [1, 5]} Output {[1, 5]} Naive Approach for merging intervals ...

**Find Peak Element** Let’s understand Find Peak Element problem. Today we have with us an array that needs its peak element. Now, you must be wondering as to what do I mean by the peak element? The peak element is one which is greater than all its neighbours. Example: Given an array of ...

**Valid Triangle Number** Problem In the Valid Triangle Number problem, we have given an array of non-negative integers. Find the number of triplets that can form a triangle. If we consider the numbers in the array as side lengths of the triangle. Example Input [ 2, 2, 3, 4 ] Output 3 Explanation We ...

**Merge Sorted Array** In merge sorted array problem we have given two sorted arrays in increasing order. In input first, we have given the number initialized to array1 and array2. These two-number are N and M. The size of array1 is equal to the sum of N and M. In array 1 first ...

**Container with Most Water** Problem description : you are given n integers (y0, y1, y2 … yn-1) at n indices (i = 0,1,2 … n-1). Integer at i-th index is yi. Now, you draw n lines on a cartesian plane each connecting points (i, yi) and (i, 0). Find the maximum volume of water ...

**Subarray Sum Equals k** Given an integer array and an integer k. Find total number of contiguous subarrays of given array whose sum of elements is equal to k. Example Input 1: arr[] = {5,0,5,10,3,2,-15,4} k = 5 Output: 7 Input 2: arr[] = {1,1,1,2,4,-2} k = 2 Output: 4 Explanation : consider example-1 ...

**Coin Change Problem** Coin Change Problem – Given some coins of different values c1, c2, … , cs (For instance: 1,4,7….). We need an amount n. Use these given coins to form the amount n. You can use a coin as many times as required. Find the total number of ways in which ...

**Find the Minimum Element in a Sorted and Rotated Array** Problem Statement In the “Find the Minimum Element in a Sorted and Rotated Array” problem we have given a sorted array a[]. This array is rotated at some unknown point, find the minimum element in this array. Input Format The first and only one line containing an integer value n. ...

**Merge Overlapping Intervals II** Problem Statement In the “Merge Overlapping Intervals II” problem we have given a set of intervals. Write a program that will merge the overlapping intervals into one and print all the non-overlapping intervals. Input Format The first line containing an integer n. Second-line containing n pairs where each pair is ...

**Maximum Subarray Sum using Divide and Conquer** Problem Statement In the “Maximum Subarray Sum using Divide and Conquer” problem we have given an array of both positive and negative integers. Write a program that will find the largest sum of the contiguous subarray. Input Format The first line containing an integer N. Second-line containing an array of ...

**Iterative Implementation of Quick Sort** Problem Statement In the “Iterative Implementation of Quick Sort” problem, we have given an array a[]. We have to sort the array using quick sort. Here, quick sort is not implemented recursively, it is implemented in an iterative manner. Input Format The first line containing an integer n. Second-line containing ...

**Shuffle a given Array** Problem Statement In the “Shuffle a given Array” problem we have given an array of integers. Write a program that shuffles the given array. That is, it will shuffle the elements in the array randomly. Input Format The first line containing an integer n. Second-line containing n space-separated integer Output ...

**Sorting a K Sorted Array** Problem Statement In the “Sorting a K Sorted Array” problem we have given an array of n elements, where each element is at most k away from its target position. Devise an algorithm that sorts in O(n log k) time. Input Format The first line containing two integer values N ...

**Maximum Product Subarray II** Problem Statement In the “Maximum Product Subarray II” problem we have given an array consisting of positive, negative integers, and also zeroes. We need to find the maximum product of the subarray. Input Format The first line containing an integer N. Second-line containing N space-separated integers. Output Format The only ...

**Maximum Sum Increasing Subsequence** Problem Statement In the “Maximum Sum Increasing Subsequence” problem we have given an array. Find the sum of the maximum subsequence of the given array, that is the integers in the subsequence are in sorted order. A subsequence is a part of an array which is a sequence that is ...

**Number of Smaller Elements on Right Side** Problem Statement In the “Number of Smaller Elements on Right Side” problem, we have given an array a[]. Find the number of smaller elements that are on the right_side of each element. Input Format The first and only one line containing an integer N. Second-line containing N space-separated integers. Output ...

**Elements Appear more than N/K times in Array** Problem Statement In the “Elements Appear more than N/K times in Array” problem we have given an integer array of size n. Find the elements which appear more than n/k times. Where k is the input value. Input Format The first and only one line containing two integers N and ...

**Find the Peak Element from an Array** Problem Statement In the “Find the Peak Element from an Array” problem we have given an input array of integers. Find a peak element. In an array, an element is a peak element, if the element is greater than both the neighbours. For corner elements, we can consider the only ...

**Rearrange Positive and Negative Numbers Alternatively in Array** Problem Statement In the “Rearrange Positive and Negative Numbers Alternatively in Array” problem we have given an array a[]. This array contains positive and negative integers. Rearrange the array in such a way that positive and negative are placed alternatively. Here, the number of positive and negative elements need not ...

**Find the Maximum Repeating Number in Array** Problem Statement In the “Find the Maximum Repeating Number in Array” problem we have given an unsorted array of size N. Given array contains numbers in range {0, k} where k <= N. Find the number that is coming the maximum number of times in the array. Input Format The ...

**Four Elements that Sum to Given** Problem Statement In four elements that sum to a given problem, we have given an array containing N elements that may be positive or negative. Find the set of four elements whose sum is equal to given value k. Input Format First-line containing an integer N. Second-line containing an array ...

**Partition Problem** Problem Statement In the Partition problem, we have given a set that contains n elements. Find whether the given set can be divided into two sets whose sum of elements in the subsets is equal. Example Input arr[] = {4, 5, 11, 9, 8, 3} Output Yes Explanation The array ...

**Find a Sorted Subsequence of size 3** Problem Statement In the given unsorted array of integers. We need to find a sorted subsequence of size 3. Let three elements be array[i], array[j], array[k] then, array[i] < array[j] < array[k] for i< j < k. If there are multiple triplets found in the array then print any one ...

**Subarray with Given Sum** Problem Statement In the subarray with the given sum problem, we have given an array containing n positive elements. We have to find the subarray in which the sum of all the elements of the subarray equal to a given_sum. Subarray is obtained from the original array by deleting some ...

**Find the Lost Element From a Duplicated Array** Problem Statement Given two arrays A and B, one array is a duplicate of the other except one element. The one element is missing from either A or B. we need to find the lost element from a duplicated array. Example 5 1 6 4 8 9 6 4 8 ...

**Rearrange given Array in Maximum Minimum Form** Problem Statement In the “Rearrange given Array in Maximum Minimum Form” problem, we have given a sorted array containing N elements. Rearrange the given sorted array of positive integers, such that alternative elements are ith max and ith min. See below for a better understanding of rearrangement of elements- Array[0] ...

**Merge Two Sorted Arrays** Problem Statement In merge two sorted arrays problem, we have given two input sorted arrays, we need to merge these two arrays such that the initial numbers after complete sorting should be in the first array and remaining in the second array. Example Input A[] = {1, 3, 5, 7, ...

**Count of Triplets With Sum Less than Given Value** Problem Statement We have given an array containing N number of elements. In the given array, Count the number of triplets with a sum less than the given value. Example Input a[] = {1, 2, 3, 4, 5, 6, 7, 8} Sum = 10 Output 7 Possible triplets are : ...

**Next Greater Element in an Array** Problem Statement Given an array, we will find the next greater element of each element in the array. If there is no next greater element for that element then we will print -1, else we will print that element. Note: Next greater element is the element that is greater and ...

**Merging Two Sorted Arrays** Problem Statement In merging two sorted arrays problem we have given two sorted arrays, one array with size m+n and the other array with size n. We will merge the n sized array into m+n sized array and print the m+n sized merged array. Example Input 6 3 M[] = ...

**Find Element Using Binary Search in Sorted Array** Problem Statement Given a sorted array, Find element using binary search in the sorted array. If present, print the index of that element else print -1. Example Input arr[] = {1, 6, 7, 8, 9, 12, 14, 16, 26, 29, 36, 37, 156} X = 6 //element to be searched ...

**Find Triplet in Array With a Given Sum** Problem Statement Given an array of integers, find the combination of three elements in the array whose sum is equal to a given value X. Here we will print the first combination that we get. If there is no such combination then print -1. Example Input N=5, X=15 arr[] = ...

**Find Duplicates in an Array in Most Efficient Way** Problem Statement Display all the elements which are duplicates in the most efficient way in O(n) and O(1) space. Given an array of size n which contains numbers from range 0 to n-1, these numbers can occur any number of times. Find duplicates in an array in the most efficient ...

**Smallest Positive Number Missing in an Unsorted Array** Problem Statement In the given unsorted array find the smallest positive number missing in an unsorted array. A positive integer doesn’t include 0. We can modify the original array if needed. The array may contain positive and negative numbers. Example a. Input array : [3, 4, -1, 0, -2, 2, 1, ...

**Move All the Zeros to the End of the Given Array** Problem Statement In the given array move all the zeros which are present in the array to the end of the array. Here there is always a way exist to insert all the number of zeroes to the end of the array. Example Input 9 9 17 0 14 0 ...

**Count Number of Occurrences in a Sorted Array** Problem Statement In the “Count Number of Occurrences in a Sorted Array” problem, we have given a sorted array. Count the number of occurrences or frequency in a sorted array of X where X is an integer. Example Input 13 1 2 2 2 2 3 3 3 4 4 ...

**Find Smallest Missing Number in a Sorted Array** Problem Statement In the “Find Smallest Missing Number in a Sorted Array” problem we have given an integer array. Find the smallest missing number in N sized sorted array having unique elements in the range of 0 to M-1, where M>N. Example Input [0, 1, 2, 3, 4, 6, 7, ...

**First Repeating Element** Problem Statement We have given an array that contains n integers. We have to find the first repeating element in the given array. If there is no repeated element then print “No repeating integer found”. Note: Repeating elements are those elements that come more than once. (Array may contain duplicates) ...

**A Product Array Puzzle** Problem Statement In a product array puzzle problem we need to construct an array where the ith element will be the product of all the elements in the given array except element at the ith position. Example Input 5 10 3 5 6 2 Output 180 600 360 300 900 ...

**Find All Pairs With a Given Difference** Problem Statement We have given an array of containing different elements or no repeated elements present in the array. Find all pairs with a given difference. If there is no any pair with given different then print “No pair with given different”. Example Input 10 20 90 70 20 80 ...

**Find the first Repeating Number in a Given Array** Problem Statement There can be multiple repeating numbers in an array but you have to find the first repeating number in a given array (occurring the second time). Example Input 12 5 4 2 8 9 7 12 5 6 12 4 7 Output 5 is the first repeating element ...

**Majority Element** Problem Statement Given a sorted array, we need to find the majority element from the sorted array. Majority element: Number occurring more than half the size of the array. Here we have given a number x we have to check it is the majority_element or not. Example Input 5 2 ...

**Find the Missing Number** Problem Statement In finding the missing number from an array of 1 to N numbers we have given an array that contains N-1 numbers. One number is missing from an array of numbers from 1 to N. We have to find the missing number. Input Format First-line containing an integer ...

## String Questions Bloomberg

**Minimum Number of Steps to Make Two Strings Anagram Leetcode Solutions** Problem Statement In this problem, we are given two strings ‘s’ & ‘t’ consisting of lower-case English characters. In one operation, we can choose any character in string ‘t’ and change it to some other character. We need to find the minimum number of such operations to make ‘t’ an ...

**Split a String in Balanced Strings Leetcode Solution** Problem Statement In this problem, we are given a string of characters, containing only ‘R’ and ‘L’. We call a string balanced if it has the same number of ‘R’s and ‘L’s. We can split the given string into disjoint substrings. The goal is to find the maximum possible number ...

**Isomorphic Strings Leetcode Solution** Problem Statement In this problem, we are given two strings, a and b. Our goal is to tell whether the two strings are isomorphic or not. Two strings are called isomorphic if and only if the characters in the first string can be replaced by any character(including itself) at all ...

**Maximum Nesting Depth of the Parentheses Leetcode Solution** Problem Statement In this problem, we are given a valid parentheses string (vps) having some numbers, some operators(e.g. +,-,*) and some parentheses(e.g. ‘(‘,’)’). Valid parentheses strings (vps) are: “” “d” where d is any number “(A)” if A is valid parentheses string “A*B” if * is any operator and A ...

**Is Subsequence Leetcode Solution** Problem Statement In this problem, we are given two different strings. The goal is to find out whether the first string is a subsequence of the second. Examples first string = "abc" second string = "mnagbcd" true first string = "burger" second string = "dominos" false Approach(Recursive) This is easy ...

**Valid Palindrome Leetcode Solution** Problem Statement Given a string, we have to determine if it is a palindrome, considering only alphanumeric characters i.e. numbers and alphabets only. We also have to ignore cases for alphabet characters. Example "A man, a plan, a canal: Panama" true Explanation: “AmanaplanacanalPanama” is a valid palindrome. "race a car" ...

**Roman to Integer Leetcode Solution** In the problem “Roman to Integer”, we are given a string representing some positive integer in its Roman numeral form. Roman numerals are represented by 7 characters that can be converted to integers using the following table: Note: The integer value of the given roman numeral will not exceed or ...

**Integer to Roman Leetcode Solution** In this problem, we are given an integer and are required to convert into roman numeral. Thus the problem is generally referred to as “Integer to Roman” and this is Integer to Roman Leetcode Solution. If someone does not know about Roman numerals. In the old times, people did not ...

**Longest Substring Without Repeating Characters** Given a string, we have to find the length of the longest substring without repeating characters. Let’s look into a few examples: Example pwwkew 3 Explanation: Answer is “wke” with length 3 aav 2 Explanation: Answer is “av” with length 2 Approach-1 for Longest Substring Without Repeating Characters Brute Force ...

**Fizz Buzz** The problem name might seem fuzzy. Fizz Buzz is a game with which children are taught about the division. So, without much hassle let’s clear the buzz around it. Problem Statement Let us write a program where for multiples of 3 you print “Fizz”, for the multiples of 5 “Buzz” ...

**Fizz Buzz Leetcode** In Fizz Buzz problem we have given a number n, print the string representation of numbers from 1 to n with the given conditions: Print “Fizz” for multiples of 3. Print “Buzz” for multiples of 5. Print “FizzBuzz” for multiples of both 3 and 5. Otherwise, print the number in ...

**Decode String** Suppose, you are given an encoded string. A string is encoded in some kind of pattern, your task is to decode the string. Let us say, < no of times string occurs > [string ] Example Input 3[b]2[bc] Output bbbcaca Explanation Here “b” occurs 3times and “ca” occur 2 times. ...

**Next Permutation** In the next permutation problem we have given a word, find the lexicographically greater_permutation of it. Example input : str = "tutorialcup" output : tutorialpcu input : str = "nmhdgfecba" output : nmheabcdfg input : str = "algorithms" output : algorithsm input : str = "spoonfeed" output : Next Permutation ...

**Letter Case Permutation** In letter case permutation we have given a string consisting of alphabets and numbers only, each character in the string can be converted into lowercase and uppercase, find out all different strings which can be obtained from different combinations of lowercase and uppercase of each character in the string. Example ...

**Longest Common Prefix using Sorting** In the Longest Common Prefix using Sorting problem we have given a set of strings, find the longest common prefix. i.e. find the prefix part that is common to all the strings. Example Input1: {“tutorialcup”, “tutorial”, “tussle”, “tumble”} Output: "tu" Input2: {"baggage", "banana", "batsmen"} Output: "ba" Input3: {"abcd"} Output: "abcd" ...

**Regular Expression Matching** In the Regular Expression Matching problem we have given two strings one (let’s assume it x) consists of only lower case alphabets and second (let’s assume it y) consists of lower case alphabets with two special characters i.e, “.” and “*”. The task is to find whether the second string ...

**Valid Parentheses** In Valid Parentheses problem we have given a string containing just the characters ‘(‘, ‘)’, ‘{‘, ‘}’, ‘[‘ and ‘]’, determine if the input string is valid. An input string is valid if: Open brackets must be closed by the same type of brackets. ( ) [ ] { } ...

**Longest Common Prefix using Trie** In the Longest Common Prefix using Trie problem we have given a set of strings, find the longest common prefix. i.e. find the prefix part that is common to all the strings. Example Input1: {“tutorialcup”, “tutorial”, “tussle”, “tumble”} Output: "tu" Input2: {"baggage", "banana", "batsmen"} Output: "ba" Input3: {"abcd"} Output: "abcd" ...

**Count and Say** Count and Say in which we have given a number N and we need to find the Nth term of the count and say sequence. Firstly we need to understand what is count and say sequence. Firstly see some terms of the sequence: 1st term is “1”. 2nd term is ...

**Find unique character in a string** In Find unique character in a string problem, we have given a string containing only lower case alphabets(a-z). We need to find the first non-repeating character in it and print the index. if no such character exists print -1. Input Format Only a single line containing string. Output Format Print ...

**Integer to Roman** Integer to Roman conversion. We have given a number N and we need to print the Roman number of N. Roman numbers are represented by the use of {I, V, X, L, C, D, M} values. Let’s see some examples for good understanding. Input Format Only a single line containing ...

**Distinct Subsequences** Given two strings S and P1, we have to count all the number of distinct subsequences of S which equals P1. Note: A subsequence of a given string is a string that we archive by deleting some characters or possible zero characters also from the original string. We can’t change ...

**Kth Non-repeating Character** Problem Statement In the “Kth Non-repeating Character” we have given a string “s”. Write a program to find out the kth non-repeating_character. If there are less than k character which is non-repeating in the string then print “-1”. Input Format The first and only one line containing a string “s”. ...

**Print all Possible Ways to Break a String in Bracket Form** Problem Statement In the “Print all Possible Ways to Break a String in Bracket Form” problem, we have given a string “s”. Find all possible ways to break the given string in bracket form. Enclose all substrings within brackets (). Input Format The first and only one line containing a ...

**Longest Common Prefix Word by Word Matching** Problem Statement In the “Longest Common Prefix using Word by Word Matching” problem, we have given N strings. Write a program to find the longest common prefix of the given strings. Input Format The first line containing an integer value N which denotes the number of strings. Next N lines ...

**Longest Common Prefix using Character by Character Matching** Problem Statement In the “Longest Common Prefix using Character by Character Matching” problem we have given an integer value N and N strings. Write a program to find the longest common prefix of the given strings. Input Format The first line containing an integer value N which denotes the number ...

**Longest Common Prefix Using Binary Search II** Problem Statement In the “Longest Common Prefix Using Binary Search II” problem we have given an integer value N and N strings. Write a program that will print the longest common prefix of given strings. If there is no common prefix then print “-1”. Input Format The first line containing ...

**Length of Longest valid Substring** Problem Statement In the “Length of Longest valid Substring” we have given a string that contains the opening and closing parenthesis only. Write a program that will find the longest valid parenthesis substring. Input Format The first and only one line containing a string s. Output Format The first and ...

**Check if a Linked list of Strings form a Palindrome** Problem Statement In the “Check if a Linked list of Strings form a Palindrome” problem we have given a linked list handling string data. Write a program to check whether the data forms a palindrom or not. Example ba->c->d->ca->b 1 Explanation: In the above example we can see that the ...

## Tree Questions Bloomberg

**Number of siblings of a given Node in n-ary Tree** Problem Statement The problem “Number of siblings of a given Node in n-ary Tree” states that you are given an n-ary Tree and a target node. Find the number of siblings of the target node. Assume that node is always present in the tree and the first node is the ...

**Binary Tree to Binary Search Tree Conversion** In binary tree to binary search tree conversion problem, we have given a binary tree convert it to Binary Search Tree without changing the structure of the tree. Example Input Output pre-order : 13 8 6 47 25 51 Algorithm We do not have to change the structure of the ...

**Sorted Array to Balanced BST** In sorted array to balanced BST problem, we have given an array in sorted order, construct a Balanced Binary Search Tree from the sorted array. Examples Input arr[] = {1, 2, 3, 4, 5} Output Pre-order : 3 2 1 5 4 Input arr[] = {7, 11, 13, 20, 22, ...

**Transform a BST to Greater sum Tree** In transform a BST to greater sum tree Given a Binary Search Tree write an algorithm to convert it to a greater sum tree, that is, transform each node to contain the sum of all the elements greater than it. Example Input Output Pre-order : 69 81 87 34 54 ...

**BST to a Tree with Sum of all Smaller Keys** In this problem we have given a Binary Search Tree, write an algorithm to convert best to a tree with sum of all smaller keys. Example Input Output Pre-order : 19 7 1 54 34 88 Naive Approach Traverse all the nodes one by one in any traversal form, and ...

**Find the node with minimum value in a Binary Search Tree** Given a Binary Search Tree, write an algorithm to find the node with the minimum value in a given binary search tree. Example Input Output 5 Naive Approach A simple approach is to do a tree traversal and find the node with the minimum value among all the nodes. This ...

**Construct Binary Tree from Given Inorder and Preorder Traversals** In this problem, we have inorder and preorder of the binary tree. We need to construct a binary tree from the given Inorder and Preorder traversals. Example Input: Inorder= [D, B, E, A, F, C] Preorder= [A, B, D, E, C, F] Output: Pre-order traversal of the tree formed by ...

**Reverse a Path in BST using Queue** In reverse a path in BST using queue problem we have given a Binary Search Tree and node, write an algorithm to reverse the path from root to the given node. Assume that the node exists in the BST. Example Input Target Node = 12 Output In-order traversal before the ...

**Level order Traversal in Spiral Form** In this problem we have given a binary tree, print its level order traversal in a spiral form. Examples Input Output 10 30 20 40 50 80 70 60 Naive Approach for Level order Traversal in Spiral Form The idea is to do a normal level order traversal using a ...

**Kth Smallest Element in a BST** In this problem, we have given a BST and a number k, find the kth smallest element in a BST. Examples Input tree[] = {5, 3, 6, 2, 4, null, null, 1} k = 3 Output 3 Input tree[] = {3, 1, 4, null, 2} k = 1 Output 1 ...

**Balanced Binary Tree** In the balanced binary tree problem, we have given the root of a binary tree. We have to determine whether or not it is height balance. Examples Input Output true Input Output: false Balanced Binary Tree Every node in a balanced binary tree has a difference of 1 or less ...

**Lowest Common Ancestor** Given the root of a binary tree and two nodes n1 and n2, find the LCA(Lowest Common Ancestor) of the nodes. Example What is Lowest Common Ancestor(LCA)? The ancestors of a node n are the nodes present in the path between root and node. Consider the binary tree shown in ...

**Binary Tree zigzag level order Traversal** Given a binary tree, print the zigzag level order traversal of its node values. (ie, from left to right, then right to left for the next level and alternate between). Example consider the binary tree given below Below is the zigzag level order traversal of the above binary tree Types ...

**Populating Next Right Pointers in Each Node** Given a Binary Tree, connect nodes that are at the same level from left to right. Structure of the Tree Node: A node of the tree contains 4 components which are data(integer value), pointers(next, left and right) of the tree node type. next pointer of a node point towards its ...

**Longest Common Prefix using Trie** In the Longest Common Prefix using Trie problem we have given a set of strings, find the longest common prefix. i.e. find the prefix part that is common to all the strings. Example Input1: {“tutorialcup”, “tutorial”, “tussle”, “tumble”} Output: "tu" Input2: {"baggage", "banana", "batsmen"} Output: "ba" Input3: {"abcd"} Output: "abcd" ...

**Validate Binary Search Tree** Problem In Validate Binary Search Tree problem we have given the root of a tree, we have to check if it is a binary search tree or not. Example : Output: true Explanation: The given tree is a binary search tree because all elements which are left to each subtree ...

**Level Order Traversal of Binary Tree** Level Order Traversal of a given binary tree is the same as the BFS of the binary tree. Do we already know about what actually BFS is? if not then don’t need to feel bad just read the whole article and visit our previous articles for better understanding. BFS is a ...

**Deletion in a Binary Tree** Do we already know about what actually Binary Tree is? Now in this post, we are focusing on how to delete a node whose value is given. We are sure that the value of the node which we want to delete is always present before deletion in BT. In Binary ...

**Unique Binary Search Trees** Firstly we have to find the total number of counts to form a unique binary search tree. After it, we construct all possible unique BST. First of all, we have to know the construction of BST. In a Binary Search Tree, the nodes present in the left subtree wrt. any ...

## Graph Questions Bloomberg

**Evaluate Division** In evaluate division problem we have given some equations, in the form, A/B = k, where A and B are strings and k is a real number. Answer some queries, if the answer does not exist return -1. Example Input: equations: a/b = 2.0 and b/c = 3.0 queries: a/c ...

**Max Area of Island** Problem Description: Given a 2D matrix, the matrix has only 0(representing water) and 1(representing land) as entries. An island in the matrix is formed by grouping all the adjacent 1’s connected 4-directionally(horizontal and vertical). Find the maximum area of the island in the matrix. Assume that all four edges of ...

**Graph Cloning** What is Graph Cloning? Today we have with us a reference to an undirected graph. What do we have to do? Returning a deep copy of the provided graph. Let us look at the structure: The Class Node: It consists of the data value and the neighbors associated with each ...

## Stack Questions Bloomberg

**Min Stack Leetcode Solution** Problem Statement Design a stack that supports push, pop, top, and retrieving the minimum element in constant time. push(x) — Push element x onto stack. pop() — Removes the element on top of the stack. top() — Get the top element. getMin() — Retrieve the minimum element in the stack. ...

**Next Greater Element I Leetcode Solution** Problem Statement In this problem, we are given two lists in which first list is subset of second list. For each element of first list, we have to find out next greater element in the second list. Example nums1 = [4,1,2], nums2 = [1,3,4,2] [-1,3,-1] Explanation: for first element of list1 i.e. for 4 there ...

**Level order Traversal in Spiral Form** In this problem we have given a binary tree, print its level order traversal in a spiral form. Examples Input Output 10 30 20 40 50 80 70 60 Naive Approach for Level order Traversal in Spiral Form The idea is to do a normal level order traversal using a ...

**Min Stack** In min stack problem we have to design a stack to implement the following functions efficiently, push(x) –> Push an element x to the stack pop() –> Removes the item on top of stack top() –> Return the element at top of stack getMin() –> Return the minimum element present ...

**Trapping Rain Water** In Trapping Rain Water problem we have given N non-negative integers representing an elevation map and the width of each bar is 1. We have to find the amount of water that can be trapped in the above structure. Example Let’s understand that by an example For the above elevation ...

**Decode String** Suppose, you are given an encoded string. A string is encoded in some kind of pattern, your task is to decode the string. Let us say, < no of times string occurs > [string ] Example Input 3[b]2[bc] Output bbbcaca Explanation Here “b” occurs 3times and “ca” occur 2 times. ...

**Binary Tree zigzag level order Traversal** Given a binary tree, print the zigzag level order traversal of its node values. (ie, from left to right, then right to left for the next level and alternate between). Example consider the binary tree given below Below is the zigzag level order traversal of the above binary tree Types ...

**Next greater element** The next greater element is a problem in which we have given an array. This array containing N values(may be positive or negative). We need to find the first greater_element in the given array on its right side. If there is no greater_element then take -1. Input Format First-line containing ...

**Next Greater Element in an Array** Problem Statement Given an array, we will find the next greater element of each element in the array. If there is no next greater element for that element then we will print -1, else we will print that element. Note: Next greater element is the element that is greater and ...

## Queue Questions Bloomberg

**Number of siblings of a given Node in n-ary Tree** Problem Statement The problem “Number of siblings of a given Node in n-ary Tree” states that you are given an n-ary Tree and a target node. Find the number of siblings of the target node. Assume that node is always present in the tree and the first node is the ...

**Find the node with minimum value in a Binary Search Tree** Given a Binary Search Tree, write an algorithm to find the node with the minimum value in a given binary search tree. Example Input Output 5 Naive Approach A simple approach is to do a tree traversal and find the node with the minimum value among all the nodes. This ...

**Reverse a Path in BST using Queue** In reverse a path in BST using queue problem we have given a Binary Search Tree and node, write an algorithm to reverse the path from root to the given node. Assume that the node exists in the BST. Example Input Target Node = 12 Output In-order traversal before the ...

**Binary Tree zigzag level order Traversal** Given a binary tree, print the zigzag level order traversal of its node values. (ie, from left to right, then right to left for the next level and alternate between). Example consider the binary tree given below Below is the zigzag level order traversal of the above binary tree Types ...

**Level Order Traversal of Binary Tree** Level Order Traversal of a given binary tree is the same as the BFS of the binary tree. Do we already know about what actually BFS is? if not then don’t need to feel bad just read the whole article and visit our previous articles for better understanding. BFS is a ...

## Matrix Questions Bloomberg

**Word Search Leetcode Solution** Problem Statement Given an m x n board and a word, find if the word exists in the grid. The word can be constructed from letters of sequentially adjacent cells, where “adjacent” cells are horizontally or vertically neighbouring. The same letter cell may not be used more than once. Example ...

**Minimum time required to rot all oranges** Problem Statement The problem “Minimum time required to rot all oranges” states that you are given a 2D array, every cell has one of the three possible values 0, 1 or 2. 0 means an empty cell. 1 means a fresh orange. 2 means a rotten orange. If a rotten ...

**Max Area of Island** Problem Description: Given a 2D matrix, the matrix has only 0(representing water) and 1(representing land) as entries. An island in the matrix is formed by grouping all the adjacent 1’s connected 4-directionally(horizontal and vertical). Find the maximum area of the island in the matrix. Assume that all four edges of ...

**Unique Paths** A m x n 2D grid is given and you are standing at the topmost and leftmost cell in the grid. i.e. the cell located at (1,1). Find the number of unique paths that can be taken to reach a cell located at (m,n) from the cell located at (1,1) ...

## Other Questions Bloomberg

**Remove Linked List Elements Leetcode Solution** Problem Statement In this problem, we are given a linked list with its nodes having integer values. We need to delete some nodes from the list which have value equal to val. The problem does not require to be solved in-place but we will discuss one such approach. Example List = ...

**Factorial Trailing Zeroes Leetcode Solution** Problem Statement In this problem we have to find out how many trailing zeroes will be there in n! Given n as input. Like there is one trailing zero in 5! 5! = 5*4*3*2*1 = 120 Example n = 3 0 Explanation: 3! = 6, no trailing zero n = 0 0 Explanation: 0! ...

**Majority Element Leetcode Solution** Problem Statement We are given an array of integers. We need to return the integer which occurs more than ⌊N / 2⌋ time in the array where ⌊ ⌋ is the floor operator. This element is called the majority element. Note that the input array always contains a majority element. ...

**Base 7 Leetcode Solution** The problem Base 7 Leetcode Solution, asks us to convert a number into a base 7 number. The given number can be negative or positive until 10 million, in both directions on the number line. The problem seems simple and is a simple conversion of a decimal number into a ...

**Palindrome Linked List Leetcode Solution** In the problem “Palindrome Linked List”, we have to check whether a given singly integer linked list is a palindrome or not. Example List = {1 -> 2 -> 3 -> 2 -> 1} true Explanation #1: The list is palindrome as all elements from the start and back are ...

**Rotate List Leetcode Solution** The problem Rotate List Leetcode Solution provides us a linked list and an integer. We are told to rotate the linked list to the right by k places. So if we rotate a linked list k places to the right, in each step we take the last element from the ...

**Pow(x, n) Leetcode Solution** The problem “Pow(x, n) Leetcode Solution” states that you are given two numbers, one of which is a floating-point number and another an integer. The integer denotes the exponent and the base is the floating-point number. We are told to find the value after evaluating the exponent over the base. ...

**Merge Two Sorted Lists Leetcode Solutions** Linked lists are quite like arrays in their linear properties. We can merge two sorted arrays to form an overall sorted array. In this problem, we have to merge two sorted linked lists in place to return a new list which contains elements of both lists in a sorted fashion. Example ...

**Permutations Leetcode Solution** The problem Permutations Leetcode Solution provides a simple sequence of integers and asks us to return a complete vector or array of all the permutations of the given sequence. So, before going into solving the problem. We should be familiar with permutations. So, a permutation is nothing but an arrangement ...

**Sqrt(x) Leetcode Solution** As the title says, we need to find the square root of a number. Let say the number is x, then Sqrt(x) is a number such that Sqrt(x) * Sqrt(x) = x. If the square root of a number is some decimal value, then we have to return the floor value of ...

**Convert Sorted Array to Binary Search Tree Leetcode Solution** Consider we are given a sorted array of integers. The goal is to build a Binary Search Tree from this array such that the tree is height-balanced. Note that a tree is said to be height-balanced if the height difference of left and right subtrees of any node in the ...

**Swap Nodes in Pairs Leetcode Solutions** The goal of this problem is to swap nodes of a given linked list in pairs, that is, swapping every two adjacent nodes. If we are allowed to swap just the value of the list nodes, the problem would be trivial. So, we are not allowed to modify the node ...

**Palindrome Number** Problem Statement the problem “Palindrome Number” states that you are given an integer number. Check if it is a palindrome or not. Solve this problem without converting the given number into a string. Example 12321 true Explanation 12321 is a palindrome number because when we reverse 12321 it gives 12321 ...

**Huffman Coding** We have a message that we want to deliver. We want the message to be of least size possible so that the costs incurred in sending the message is low. Here we use the Huffman Coding concept to reduce the size of the message. Let’s assume that we have the ...

**Target Sum** “Target Sum” is a special problem for all the DPHolics I have with me today. There ain’t no need to worry I am going to abandon the rest of my lovely readers. We all have gone through the classic KnapSack problem where we try to find the maximum number of ...

**Merge K Sorted Linked Lists** Merge K sorted linked lists problem is so famous as per the interview point of view. This question asks so many times in big companies like Google, Microsoft, Amazon, etc. As the name suggests we’ve been provided with k sorted linked lists. We have to merge them together into a ...

**Merge Two Sorted Linked Lists** In merge two sorted linked lists we have given head pointer of two linked lists, merge them such that a single linked list is obtained which has nodes with values in sorted order. return the head pointer of the merged linked list. Note: merge the linked list in-place without using ...

**Word Break** Word Break is a problem that beautifully illustrates a whole new concept. We have all heard of compound words. Words made up of more than two words. Today we have a list of words and all we’ve got to do is check if all the words from the dictionary can ...

**Merge Two Sorted Lists Leetcode** What is merge two sorted lists problem on leetcode? This is so interesting question asked so many times in compnies like Amazon, Oracle, Microsoft, etc. In this problem(Merge Two Sorted Lists Leetcode), we have given two linked lists. Both linked lists are in increasing order. Merge both linked list in ...

**LRU Cache Implementation** Least Recently Used (LRU) Cache is a type of method which is used to maintain the data such that the time required to use the data is the minimum possible. LRU algorithm used when the cache is full. We remove the least recently used data from the cache memory of ...

**Add two numbers** Add two numbers is a problem in which we have given two non-empty linked list representing a non-negative integer. The digit are store in reverse order and every node must contain only a single digit. Add the two numbers and print the result by using a linked list. Input Format ...

**Climbing stairs** Problem Statement The problem “Climbing stairs” states that you are given a staircase with n stairs. At a time you can either climb one stair or two stairs. How many numbers of ways to reach the top of the staircase? Example 3 3 Explanation There are three ways to climb ...

**Serialize and Deserialize Binary Tree** We have given a binary tree containing N number of nodes where each node has some value. We need to serialize and deserialize the binary tree. Serialize The process of storing a tree in a file without disturbing its structure is called serialization. DeserializeSerialize and Deserialize Binary Tree The process ...

**Maximum Length of Chain Pairs** Problem Statement In the maximum length of chain pairs problem we have given n pairs of numbers, find the longest chain in which (c, d) can follow (a, b) if b < c. In the given pairs the first element is always smaller than the second. Example Input [{12, 14}, ...

**Find Pair with Given Difference** Problem Statement In the given unsorted array, find the pair of elements in the given array with given difference n. Example Input arr[] = {120, 30, 70, 20, 5, 6}, difference(n) = 40 Output [30, 70] Explanation Here the difference of 30 and 70 is equal to the value of ...