Top 2024 Interview Questions Per Company

Top Interview Problems to Prepare for in 2024: A Comprehensive Guide

For tech enthusiasts and aspiring developers, nailing a technical interview is a crucial step toward landing their dream job at top companies like Meta, Google, Amazon, and more. To help you prepare effectively, we’ve compiled a list of the most frequently asked data structures and algorithms (DSA) problems in recent interviews. These questions are sourced from real interview experiences at leading tech firms, ensuring you’re well-equipped to tackle challenging coding rounds.

Key Insights: Popular Problems by Company

1. Meta

Meta, known for its innovative platforms, focuses on a variety of DSA problems. Some of the most commonly asked questions include:

• Move All Zeroes to End: Rearranging an array such that zeroes are moved to the end while maintaining the relative order of non-zero elements.
• Valid Expression: Determining if a string of parentheses is valid.
• Find the Number of Islands: Counting the number of distinct landmasses in a grid where each cell represents land or water.
• Top View of Binary Tree: Printing the top view of a binary tree, which involves traversing the tree level by level and recording the first node encountered at each level.
• Is Valid Sudoku: Checking if a 9×9 Sudoku grid is valid according to Sudoku rules.
• Nodes at Given Distance in Binary Tree: Finding all nodes in a binary tree that are at a specified distance from a given node.

Practicing these problems will help you build a solid foundation for interviews at Meta.

2. Google

Google’s interview process is renowned for its challenging algorithmic questions. Some key problems to prepare include:

• Root to Leaf Path Sum: Checking if there exists a path from the root to a leaf in a binary tree where the sum of node values equals a given target.
• Minimum Platforms: Determining the minimum number of platforms required for a railway station to accommodate all trains without any overlap.
• Minimum Window Substring: Finding the smallest window in a string that contains all characters of a given substring.
• Smallest Window Containing All Characters: Similar to the minimum window substring problem but focused on any set of characters.

These problems test your ability to handle arrays, trees, and strings efficiently.

3. Amazon

Amazon’s technical interviews often include problems that focus on real-world applications. Some notable questions include:

• Left View of Binary Tree: Printing the left view of a binary tree, which involves traversing the tree level by level and recording the first node encountered at each level.
• Faulty Keyboard: Determining which keys on a keyboard are faulty based on their malfunctioning patterns.
• Kth Element in Matrix: Finding the kth smallest element in a sorted matrix where each row is sorted in ascending order.
• Bipartite Graph: Checking if a given graph is bipartite, meaning it can be divided into two sets of vertices such that no two vertices within the same set are adjacent.

These problems will help you demonstrate your proficiency in tree traversal and graph algorithms.

4. Apple

Apple’s interviews are known for their focus on problem-solving and attention to detail. Some key problems to prepare include:

• Word Ladder I & II: Converting a word into another word by changing one letter at a time, with each intermediate word being valid. The second part involves finding the shortest transformation sequence.
• Solve the Sudoku: Developing an algorithm to solve a partially filled Sudoku grid.
• Union of Arrays with Duplicates: Finding the union of two arrays, including duplicate elements.
• Spirally Traversing a Matrix: Printing elements of a matrix in a spiral order, starting from the top-left corner and moving inwards.

These problems require a combination of clever algorithms and efficient traversal techniques.

5. Microsoft

Microsoft’s interview process often includes a mix of classic and innovative problems. Some stand-out questions include:

• Anagram Detection: Checking if two strings are anagrams of each other.
• Delete in a Singly Linked List: Implementing a function to delete a node from a singly linked list.
• Next Permutation: Finding the next higher permutation of a given number.
• Kth Largest in a Stream: Determining the kth largest element from a stream of numbers.
• Cycle in a Directed Graph: Detecting if a directed graph contains a cycle.

These problems will test your understanding of linked lists, permutations, and graph theory.

6. Walmart

Walmart’s technical interviews often involve problems that require practical application of DSA concepts. Some key problems include:

• Minimum Window Substring: Finding the smallest window in a string that contains all characters of a given substring.
• Smallest Window Containing All Characters: Similar to the minimum window substring problem but focused on any set of characters.

These problems will help you demonstrate your ability to handle substring and array manipulations.

7. Atlassian

Atlassian’s interview process is known for its focus on problem-solving and real-world applications. Some key problems include:

• Root to Leaf Path Sum: Checking if there exists a path from the root to a leaf in a binary tree where the sum of node values equals a given target.
• Minimum Platforms: Determining the minimum number of platforms required for a railway station to accommodate all trains without any overlap.

These problems require a solid understanding of tree traversal and greedy algorithms.

8. Samsung

Samsung’s interviews often include a mix of classic and innovative problems. Some stand-out questions include:

• Left View of Binary Tree: Printing the left view of a binary tree, which involves traversing the tree level by level and recording the first node encountered at each level.
• Faulty Keyboard: Determining which keys on a keyboard are faulty based on their malfunctioning patterns.

These problems will test your understanding of tree traversal and array manipulations.

9. Zoho

Zoho’s interview process often involves problems that require efficient use of data structures. Some key problems include:

• Stock Buy and Sell – Max One Transaction Allowed: Determining the maximum profit that can be achieved by buying and selling a stock once.
• Union of Arrays with Duplicates: Finding the union of two arrays, including duplicate elements.
• Spirally Traversing a Matrix: Printing elements of a matrix in a spiral order, starting from the top-left corner and moving inwards.

These problems will help you demonstrate your ability to handle arrays, matrices, and financial transactions.

10. Flipkart

Flipkart’s technical interviews often include a mix of classic and innovative problems. Some stand-out questions include:

• Anagram Detection: Checking if two strings are anagrams of each other.
• Maximum Product Subarray: Finding the contiguous subarray within a one-dimensional array of numbers that has the largest product.
• Search in Rotated Sorted Array: Searching for a target value in a sorted array that has been rotated an unknown number of times.
• House Robber: Determining the maximum sum of non-adjacent elements in an array.
• Rotten Oranges: Simulating the process of oranges rotting in a grid, where each minute, any fresh orange adjacent to a rotten orange becomes rotten.
• Trapping Rain Water: Calculating how much water can be trapped after raining on a terrain represented by an array of elevations.
• Matrix Chain Multiplication: Determining the optimal way to parenthesize a chain of matrices to minimize the number of scalar multiplications.

These problems will test your understanding of arrays, strings, matrices, and dynamic programming.

11. Adobe

Adobe’s interviews are known for their focus on problem-solving and attention to detail. Some key problems include:

• Delete in a Singly Linked List: Implementing a function to delete a node from a singly linked list.
• Next Permutation: Finding the next higher permutation of a given number.
• Kth Largest in a Stream: Determining the kth largest element from a stream of numbers.
• Cycle in a Directed Graph: Detecting if a directed graph contains a cycle.
• Print Anagrams Together: Rearranging an array of strings so that all anagrams appear together.
• Ways to Reach the n’th Stair: Calculating the number of distinct ways to reach the nth stair using either