20+ Full Stack Engineer Interview Questions and Answers for Freshers

Q1. Find All Subsets

Given an array arr consisting of 'N' distinct integers, your task is to generate all possible non-empty subsets of the given array.

You can return the subsets in any order.

Input:

The first lin...read more

Q2. Longest Palindromic Subsequence Problem Statement

Given a string A consisting of lowercase English letters, determine the length of the longest palindromic subsequence within A.

Explanation:

• A subsequence is d...read more

Q3. Reverse Linked List Problem Statement

Given a singly linked list of integers, return the head of the reversed linked list.

Example:

Initial linked list: 1 -> 2 -> 3 -> 4 -> NULL
Reversed linked list: 4 -> 3 -> 2...read more

Q4. Next Smallest Palindrome Problem Statement

Given a string representation of a number 'S', determine the smallest palindrome that is strictly greater than this number 'N'.

Example:

Input:

3
2
99
3
123
4
4567

Output:

1...read more

Q6. Count Subarrays with Sum Divisible by K

Given an array ARR and an integer K, your task is to count all subarrays whose sum is divisible by the given integer K.

Input:

The first line of input contains an integer...read more

Q8. Maximum Size Rectangle Sub-matrix with All 1's Problem Statement

You are provided with an N * M sized binary matrix 'MAT' where 'N' denotes the number of rows and 'M' denotes the number of columns. Your task is...read more

Q9. Minimum Operations to Equalize Array

Given an integer array ARR of length N where ARR[i] = (2*i + 1), determine the minimum number of operations required to make all the elements of ARR equal. In a single opera...read more

Q10. Level Order Traversal Problem Statement

Given a binary tree of integers, return the level order traversal of the binary tree.

Input:

The first line contains an integer 'T', representing the number of test cases...read more

Q11. Next Greater Node in Linked List Problem Statement

In a set of linked ninja villages, the goal is to determine if a stronger ninja exists in the nearest village linked ahead. Given a linked list of 'N' integers...read more

Q12. Count the Number of Ones Problem Statement

Given an integer N, calculate the total number of times the digit '1' appears in each number from 0 to N inclusive.

Input:

T (number of test cases)
Each test case conta...read more

Q14. Count Distinct Substrings

You are provided with a string S. Your task is to determine and return the number of distinct substrings, including the empty substring, of this given string. Implement the solution us...read more

Q15. Edit Distance Problem Statement

Given two strings S and T with lengths N and M respectively, your task is to find the "Edit Distance" between these strings.

The Edit Distance is defined as the minimum number of...read more

Q16. Rank from Stream Problem Statement

Given an array of integers ARR and an integer K, determine the rank of the element ARR[K].

Explanation:

The rank of any element in ARR is defined as the number of elements sma...read more

Q17. Merge Intervals Problem Statement

You are provided with 'N' intervals, each containing two integers denoting the start time and end time of the interval.

Your task is to merge all overlapping intervals and retu...read more

Q18. Longest Subarray Zero Sum Problem Statement

Given an array of integers arr, determine the length of the longest contiguous subarray that sums to zero.

Input:

N (an integer, the length of the array)
arr (list of ...read more

Q19. Can you provide examples of OOP concepts using code, including coding for all the principles of Object-Oriented Programming?