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] …

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Kth Largest Element in a Stream Leetcode Solution

Problem Statement   In this problem, we have to design a class KthLargest() that initially has an integer k and an array of integers. We need to write a parameterized constructor for it when an integer k and array nums are passed as arguments. The class also has a function add(val) that adds …

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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 = …

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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 …

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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 …

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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 …

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Excel Sheet Column Title Leetcode Solution

Problem Statement   In this problem a positive integer is given which represents a column number of an Excel sheet, we have to return its corresponding column title as appear in an Excel sheet. Example #1 28 “AB” #2 701 “ZY” Approach   This problem is the reverse of the problem in …

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