Walmart Labs has a long history of transforming retail and using technology to deliver innovations that improve how the world shops and empower our 2.2 million associates. It began with Sam Walton and continues today with Global Tech associates working together to power Walmart and lead the next retail disruption. We’re a high-performing, primarily virtual workforce that is human-led and tech-empowered. Our world-class software engineers, data scientists and engineers, cybersecurity professionals, product managers, and business service professionals work with top talent on cutting-edge technologies that create unique and innovative experiences for our associates, customers, and members across Walmart, Sam’s Club, and Walmart International. At Walmart Global Tech, one line of code or bold idea can make life easier for hundreds of millions of people – talk about epic impact at a global scale.

It has got a 4.1* rating on Glassdoor and is considered one of the best product-based companies. It is highly regarded for its work-life balance.

They provide good training as well which will be beneficial in future too. You can practice the below Walmart Labs Interview Questions for the interview. We have collected past frequently asked Walmart Labs Interview Questions for your reference.

Categories of Questions

## Walmart Labs Array Questions

**Question 1. 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 ...

**Question 2. 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 ...

**Question 3. 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 ...

**Question 4. Kth largest element in an Array Leetcode Solutions** In this problem, we have to return the kth largest element in an unsorted array. Note that the array can have duplicates. So, we have to find the Kth largest element in the sorted order, not the distinct Kth largest element. Example A = {4 , 2 , 5 , 3 ...

**Question 5. XOR Operation in an Array Leetcode Solution** Problem Statement In this problem we have to do XOR Operation in an Array of size n in which each element is equal to (start + 2*i) where i is the index of the element (0-indexed) and value of start is given. We have to return the bitwise XOR of ...

**Question 6. Find Index of Closing Bracket for a Given Opening Bracket in an Expression** Problem Statement Given a string s of length/size n and an integer value representing the index of an opening square bracket. Find index of closing bracket for a given opening bracket in an expression. Example s = "[ABC[23]][89]" index = 0 8 s = "[C-[D]]" index = 3 5 s ...

**Question 7. Growable array based stack** Problem Statement Growable array-based stack is used in cases of “stack full”. Here the old array is replaced with the new bigger one. The size of the new array is decided using these two strategies- Tight Strategy – In this case, a constant amount say c is added to the ...

**Question 8. Largest Sum Contiguous Subarray** Problem Statement You are given an array of integers. The problem statement asks to find out the largest sum contiguous subarray. This means nothing but to find a subarray (continuous elements) which has the largest sum among all other subarrays in the given array. Example arr[] = {1, -3, 4, ...

**Question 9. 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, ...

**Question 10. Trapping Rain Water LeetCode Solution** In the Trapping Rain Water LeetCode 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 ...

**Question 11. 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}; ...

**Question 12. 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 ...

**Question 13. Degree of an array** Problem Statement In the Degree of an array problem we have given a non-empty array of non-negative integers nums, the degree of this array is defined as the maximum frequency of any one of its elements. Your task is to find the smallest possible length of a (contiguous) subarray of nums, ...

**Question 14. 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 ...

**Question 15. 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 ...

**Question 16. 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 ...

**Question 17. 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 ...

**Question 18. 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, ...

**Question 19. 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 : ...

**Question 20. 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[] = ...

**Question 21. 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[] = ...

**Question 22. Sort 0s 1s and 2s in an Array** Problem Statement Given an array containing N elements where elements of the array are 0,1 or 2. Sort or Segregate 0s 1s and 2s in an array. Arrange all zeros in the first half, all ones in the second half and all twos in the third half. Example Input 22 ...

**Question 23. 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, ...

**Question 24. 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 ...

**Question 25. 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 ...

**Question 26. 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 ...

## Walmart Labs String Questions

**Question 27. 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 ...

**Question 28. Letter Combinations of a Phone Number** In letter combinations of a phone number problem, we have given a string containing numbers from 2 to 9. The problem is to find all the possible combinations that could be represented by that number if every number has some letters assigned to it. The assignment of the number is ...

**Question 29. Longest Substring Without Repeating Characters LeetCode Solution** Longest Substring Without Repeating Characters LeetCode Solution – 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 ...

**Question 30. Find Index of Closing Bracket for a Given Opening Bracket in an Expression** Problem Statement Given a string s of length/size n and an integer value representing the index of an opening square bracket. Find index of closing bracket for a given opening bracket in an expression. Example s = "[ABC[23]][89]" index = 0 8 s = "[C-[D]]" index = 3 5 s ...

**Question 31. Check if Two Expressions With Brackets are Same** Given two strings s1 and s2 representing expressions containing addition operator, subtraction operator, lowercase alphabets, and parenthesis. Check if two expressions with brackets are the same. Example Input s1 = “-(a+b+c)” s2 = “-a-b-c” Output Yes Input s1 = “a-b-(c-d)” s2 = “a-b-c-d” Output No Algorithm to Check if Two ...

**Question 32. Check for Balanced Parentheses in an Expression** Given a string s of length n. Check whether there is a closing parenthesis for every opening parentheses i.e. if all the parentheses are balanced. In other words, we can also say that, if we have a ‘}’, ‘)’ and ‘]’ for every ‘{‘, ‘(‘ and ‘[‘ respectively, the expression ...

**Question 33. Balanced Expression with Replacement** In Balanced Expression with Replacement problem we have given a string s containing parenthesis i.e. ‘(‘, ‘)’, ‘[‘, ‘]’, ‘{‘, ‘}’. The string also contains x at some places as a replacement of parenthesis. Check if the string can be converted into an expression with valid parenthesis after replacing all ...

**Question 34. Perfect Reversible String** Problem Statement In the “Perfect Reversible String” problem we have given a string “s”. Check that if reverses of all possible substrings of the input string are present in the string or not. If present it’s a perfectly reversible_string. Input Format The first and only one line contain a string ...

## Walmart Labs Tree Questions

**Question 35. Bottom View of a Binary Tree** Problem Statement The problem “Bottom View of a Binary Tree” states that you are given a binary tree and now you need to find the bottom view for the given tree. When we see a tree from the downward direction. The nodes which are visible to us is the bottom ...

**Question 36. A program to check if a binary tree is BST or not** Problem Statement “A program to check if a binary tree is BST or not” states that you are given a binary tree and you need to check if the binary tree satisfies the properties of the binary search tree. So, the binary tree has the following properties: The left subtree ...

**Question 37. Print a Binary Tree in Vertical Order** In this problem, we have given a pointer denoting the root of the binary tree and your task is to print the binary tree in the vertical order. Example Input 1 / \ 2 3 / \ / \ 4 5 6 7 \ \ 8 9 Output 4 2 ...

**Question 38. Top View of Binary Tree** The top view of a binary tree is the set of nodes visible when the tree is viewed from the top. Given a binary tree, the Output top view of the binary tree from the left-most horizontal level to the rightmost horizontal level. Example Example 1 Example 2 Types of ...

## Walmart Labs Stack Questions

**Question 39. Find Index of Closing Bracket for a Given Opening Bracket in an Expression** Problem Statement Given a string s of length/size n and an integer value representing the index of an opening square bracket. Find index of closing bracket for a given opening bracket in an expression. Example s = "[ABC[23]][89]" index = 0 8 s = "[C-[D]]" index = 3 5 s ...

**Question 40. Growable array based stack** Problem Statement Growable array-based stack is used in cases of “stack full”. Here the old array is replaced with the new bigger one. The size of the new array is decided using these two strategies- Tight Strategy – In this case, a constant amount say c is added to the ...

**Question 41. Check if Two Expressions With Brackets are Same** Given two strings s1 and s2 representing expressions containing addition operator, subtraction operator, lowercase alphabets, and parenthesis. Check if two expressions with brackets are the same. Example Input s1 = “-(a+b+c)” s2 = “-a-b-c” Output Yes Input s1 = “a-b-(c-d)” s2 = “a-b-c-d” Output No Algorithm to Check if Two ...

**Question 42. 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 ...

**Question 43. Queue using Stacks** In queue using a stack problem, we have to implement the following functions of a queue using the standard functions of stack data structure, Enqueue: Add an element to the end of the queue Dequeue: Remove an element from the start of the queue Example Input: Enqueue(5) Enqueue(11) Enqueue(39) Dequeue() ...

**Question 44. Check for Balanced Parentheses in an Expression** Given a string s of length n. Check whether there is a closing parenthesis for every opening parentheses i.e. if all the parentheses are balanced. In other words, we can also say that, if we have a ‘}’, ‘)’ and ‘]’ for every ‘{‘, ‘(‘ and ‘[‘ respectively, the expression ...

**Question 45. Balanced Expression with Replacement** In Balanced Expression with Replacement problem we have given a string s containing parenthesis i.e. ‘(‘, ‘)’, ‘[‘, ‘]’, ‘{‘, ‘}’. The string also contains x at some places as a replacement of parenthesis. Check if the string can be converted into an expression with valid parenthesis after replacing all ...

**Question 46. Trapping Rain Water LeetCode Solution** In the Trapping Rain Water LeetCode 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 ...

## Walmart Labs Queue Questions

**Question 47. Queue using Stacks** In queue using a stack problem, we have to implement the following functions of a queue using the standard functions of stack data structure, Enqueue: Add an element to the end of the queue Dequeue: Remove an element from the start of the queue Example Input: Enqueue(5) Enqueue(11) Enqueue(39) Dequeue() ...

## Walmart Labs Other Questions

**Question 48. Meeting Rooms II LeetCode Solution** Problem Statement The Meeting Rooms II LeetCode Solution – “Meeting Rooms II” states that you are given an array of meeting time intervals “intervals” where “intervals[i] = [ start[i], end[i] ]”, return the minimum number of conference rooms required. Example: intervals = [[0,30],[5,10],[15,20]] 2 Explanation: Meeting one can be done ...

**Question 49. Subarray Sum Equals K LeetCode Solution** Problem Statement The Subarray Sum Equals K LeetCode Solution – “Subarray Sum Equals K” states that you are given an array of integers “nums” and an integer ‘k’, return the total number of continuous subarrays whose sum equals to ‘k’. Example: nums = [1, 2, 3], k=3 2 Explanation: There ...

**Question 50. Longest Palindromic Substring LeetCode Solution** Problem Statement The Longest Palindromic Substring LeetCode Solution – “Longest Palindromic Substring” states that You are Given a string s, return the longest palindromic substring in s. Note: A palindrome is a word that reads the same backward as forwards, e.g. madam. Example: s = "babad" "bab" Explanation: All ...

**Question 51. LRU Cache LeetCode Solution** Question Design a data structure that follows the constraints of a Least Recently Used (LRU) cache. Implement the LRUCache class: LRUCache(int capacity) Initialize the LRU cache with positive size capacity. int get(int key) Return the value of the key if the key exists, otherwise return -1. void put(int key, int value) Update the value of the key if the key exists. Otherwise, add the key-value pair to ...

**Question 52. 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. ...

**Question 53. 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 ...

**Question 54. House Robber II Leetcode Solution** In the “House Robber II” problem, a robber wants to rob money from different houses. The amount of money in the houses is represented through an array. We need to find the maximum sum of money that can be made by adding the elements in a given array according to ...

**Question 55. Union and Intersection of two Linked Lists** Given two linked lists, create another two linked lists to get union and intersection of the elements of existing lists. Example Input: List1: 5 → 9 → 10 → 12 → 14 List2: 3 → 5 → 9 → 14 → 21 Output: Intersection_list: 14 → 9 → 5 Union_list: ...

**Question 56. Find the Smallest Divisor given a Threshold Leetcode Solution** This post is on Find the Smallest Divisor given a Threshold Leetcode Solution Problem statement In the problem ” Find the Smallest Divisor Given a Threshold” we are given a nums array and a threshold value. A variable “result” is defined as the sum of all answers when elements in ...

**Question 57. Minimum number of jumps to reach end** Problem Statement Suppose you have an array of integers and each element of an array indicates each number as maximum jumps that can be taken from that point. Your task is to find out the minimum number of jumps to reach end, i.e. minimum of jumps that can be taken ...

**Question 58. K-th Distinct Element in an Array** You are given an integer array A, print k-th distinct element in an array. The given array may contain duplicates and the output should print k-th distinct element among all unique elements in an array. If k is more than a number of distinct elements, then report it. Example Input: ...

**Question 59. 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 ...

**Question 60. 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 ...

**Question 61. Alien Dictionary** Alien Dictionary is a type of problem in which we have N-words and they are sorted in alien dictionary order. We need to find the order of the characters. The alien language is also used the lowercase letters but the order of the letters is different. Let’s see how we ...

**Question 62. 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 ...