Categories of Questions

## Array Questions American Express

**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 ...

**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 ...

**Maximum Sum of Non Consecutive Elements** Problem Statement In the “Maximum Sum of Non Consecutive Elements” given array, you need to find the maximum sum of non-consecutive elements. You can not add immediate neighbor numbers. For example [1,3,5,6,7,8,] here 1, 3 are adjacent so we can’t add them, and 6, 8 are not adjacent so we ...

## String Questions American Express

**Convert a String that is Repetition of a Substring of Length K** Problem Statement In the “Convert a String that is Repetition of a Substring of Length K” problem we have given a string “s” and an integer “k”. Write a program to check whether is it possible to convert it to a string that is the repetition of a substring with ...

## Tree Questions American Express

**Check whether a given Binary Tree is Complete or not** Problem Statement The problem “Check whether a given Binary Tree is Complete or not” states that you are given the root of a binary tree, check whether the tree is complete or not. A complete Binary Tree has all its levels filled except for the last level and the nodes ...

**Convert a normal BST to Balanced BST** Problem Statement Given a Binary Search Tree(BST), write an algorithm to convert the BST to a Balanced Binary Search Tree. A balanced Binary Search tree is nothing but a binary search tree whose difference between the height of left subtree and right subtree is less than or equal to 1. ...

## Stack Questions American Express

**Check if a queue can be sorted into another queue using a stack** Problem Statement The problem “Check if a queue can be sorted into another queue using a stack” states that you are given a queue containing n elements, the elements in the queue are a permutation of numbers 1 to n. Check if this queue can be arranged in increasing order ...

## Queue Questions American Express

**Implementation of Deque using Doubly Linked List** Problem Statement The problem “Implementation of Deque using Doubly Linked List” states that you need to implement the following functions of Deque or Doubly Ended Queue using a doubly linked list, insertFront(x) : Add element x at the starting of Deque insertEnd(x) : Add element x at the end of ...

**Check whether a given Binary Tree is Complete or not** Problem Statement The problem “Check whether a given Binary Tree is Complete or not” states that you are given the root of a binary tree, check whether the tree is complete or not. A complete Binary Tree has all its levels filled except for the last level and the nodes ...

**Check if a queue can be sorted into another queue using a stack** Problem Statement The problem “Check if a queue can be sorted into another queue using a stack” states that you are given a queue containing n elements, the elements in the queue are a permutation of numbers 1 to n. Check if this queue can be arranged in increasing order ...

**Smallest Multiple of a Given Number** In the smallest multiple of a given number made of digits 0 and 9 only problem we have given a number n, find the smallest number made from digits 0 and 9 that is divisible by n. Assume that the answer will not exceed 106. Examples Input 3 Output 9 ...

## Other Questions American Express

**Find the point where a monotonically increasing function becomes positive first time** Problem Statement In the “Find the point where a monotonically increasing function becomes positive first time” we have given a function “int f(unsigned int x)” which takes a non-negative integer ‘x’ as input and returns an integer as output. The function is monotonically increasing with respect to the value of x, i.e., the ...