30+ Walmart Interview Questions and Answers for Freshers

Working code with edge cases is code that has been tested with extreme inputs to ensure it functions correctly.

• Edge cases are inputs that are unlikely to occur but can cause unexpected behavior if not handled properly.

• Examples of edge cases include empty inputs, null values, and inputs at the limits of the data type's range.

• Working code with edge cases should be thoroughly tested to ensure it functions correctly in all scenarios.

Use matrix exponentiation to efficiently compute the Nth Fibonacci number modulo 10^9 + 7.

• Implement matrix exponentiation to calculate Fibonacci numbers efficiently.

• Use the formula F(n) = F(n-1) + F(n-2) with initial values F(1) = F(2) = 1.

• Return the result modulo 10^9 + 7 to handle large Fibonacci numbers.

• Optimize the solution to achieve better than O(N) time complexity.

Determine if two strings are similar based on given conditions.

• Check if the strings are equal first.

• Then check if the strings can be divided into two halves with similar patterns.

• Return 1 if the strings are similar, 0 otherwise.

Calculate the sum of leaf nodes at the deepest level of a binary tree.

• Traverse the binary tree to find the deepest level of leaf nodes.

• Sum the leaf nodes at the deepest level.

• Handle null nodes represented by -1.

• Ensure the sum fits within a 32-bit integer.

Check if a permutation of a string can form a palindrome.

• Create a frequency map of characters in the string.

• Count the number of characters with odd frequencies.

• If there is at most one character with odd frequency, return true.

• Otherwise, return false.

Check if a given word is present in a sentence as a complete word.

• Split the sentence into words using spaces as delimiter.

• Check if the given word matches any of the words in the sentence.

• Ensure that the word is not just a substring of another word in the sentence.

Recursively remove consecutive duplicates from a given string.

• Use recursion to check for consecutive duplicates in the string.

• If current character is same as next character, skip the next character.

• Repeat the process until no consecutive duplicates are found.

Use recursion to print n natural numbers in C++ without semicolon.

• Define a function to print natural numbers recursively.

• Call the function inside main function with n as argument.

• Base case: if n is less than 1, return.

• Print n and call the function with n-1 as argument.

Find the number with the maximum frequency in an array of integers.

• Create a hashmap to store the frequency of each element in the array.

• Iterate through the array to update the frequency count.

• Find the element with the maximum frequency and return it.

• If multiple elements have the same maximum frequency, return the one with the lowest index.

Develop a take home project involving fetching data from APIs

• Create a project that fetches data from a public API such as weather forecast or news articles

• Use libraries like Axios or Fetch API to make API calls

• Display the fetched data in a user-friendly interface

• Implement error handling for failed API calls

The task is to find the total number of ways to make change for a specified value using given denominations.

• Use dynamic programming to solve this problem efficiently.

• Create a 2D array to store the number of ways to make change for each value using different denominations.

• Initialize the base cases and then iterate through the denominations to fill up the array.

• The final answer will be in the last cell of the array corresponding to the specified value.

Find the maximum depth of a binary tree given its level order traversal.

• Traverse the tree level by level and keep track of the depth using a queue data structure.

• For each level, increment the depth by 1 until all nodes are processed.

• Return the maximum depth encountered during traversal as the final result.

• Example: For input [5, 10, 15, 20, -1, 25, 30, -1, 40, -1, -1, -1, -1, 45], the maximum depth is 7.

Sliding window maximum problem where we find maximum element in each window of size K.

• Use a deque to store indices of elements in decreasing order within the window.

• Pop elements from the deque that are out of the current window.

• Add the maximum element to the result for each window.

Validate if a given binary tree is a Binary Search Tree (BST) or not.

• Check if the left subtree of a node contains only nodes with data less than the node's data.

• Check if the right subtree of a node contains only nodes with data greater than the node's data.

• Recursively check if both the left and right subtrees are also binary search trees.

• Example: For each node, ensure all nodes in its left subtree are less and all nodes in its right subtree are greater.

Identify the duplicate integer in an array of size N containing numbers between 1 and N-1.

• Iterate through the array and keep track of the frequency of each element using a hashmap.

• Return the element with a frequency greater than 1 as the duplicate integer.

• Ensure the constraints are met and a duplicate number is guaranteed to be present in the array.

Given an array of digits, find the maximum number that can be achieved by performing at most one swap.

• Iterate through the array to find the maximum digit.

• If the maximum digit is already at the beginning, find the next maximum digit and swap them.

• If the maximum digit is not at the beginning, swap it with the digit at the beginning.

Find the next smaller element for each element in an array.

• Iterate through the array from right to left and use a stack to keep track of elements.

• Pop elements from the stack until a smaller element is found or the stack is empty.

• If a smaller element is found, that is the next smaller element. If the stack is empty, there is no smaller element.

Given a string, select smallest character from first K characters, remove it, and append to new string until original string is empty.

• Iterate through the string, selecting the smallest character from the first K characters each time.

• Remove the selected character from the original string and append it to the new string.

• Repeat the process until the original string is empty.

• Return the final new string formed after the operations.

Find the equilibrium index of an array where sum of elements on left equals sum on right.

• Iterate through the array and calculate prefix sum and suffix sum at each index.

• Compare prefix sum and suffix sum to find equilibrium index.

• Return the left-most equilibrium index found.

The problem is to color a graph with two colors such that no two connected vertices have the same color.

• Use a graph coloring algorithm such as Depth First Search (DFS) or Breadth First Search (BFS).

• Start with an arbitrary vertex and color it with one color (e.g., blue).

• Color all its adjacent vertices with the other color (e.g., red).

• Continue this process for all connected components of the graph.

• If at any point, you encounter two adjacent vertices with the same color, it is n...read more

Design a scalable and fault-tolerant system for a social media platform

• Use microservices architecture to break down the system into smaller, independent services

• Implement load balancing to distribute traffic evenly across servers

• Utilize caching mechanisms to improve performance and reduce database load

• Implement redundancy and failover mechanisms to ensure high availability

• Use monitoring and alerting tools to detect and respond to issues proactively

The Josephus Problem involves eliminating every Kth person in a circle of N individuals until only one person remains. Determine the position of the last person standing.

• Use a circular linked list to simulate the elimination process efficiently

• Implement a function to find the position of the last person standing based on the given N and K values

• Consider edge cases such as when N=1 or K=1

• Optimize the solution to handle large values of N and K efficiently

Design a calculator app with basic arithmetic operations.

• Include basic arithmetic operations like addition, subtraction, multiplication, and division.

• Design a user-friendly interface with large buttons for numbers and operations.

• Allow users to input numbers using both keypad and touch screen.

• Implement error handling for division by zero and other invalid inputs.

Design a URL shortener system

• Generate a unique short code for each URL

• Store the mapping of short code to original URL in a database

• Redirect users from short URL to original URL

• Consider scalability and performance

• Implement analytics to track usage statistics

To improve sales and marketing, I would focus on creating targeted campaigns and utilizing data analytics to track performance.

• Conduct market research to identify target audience and their needs

• Develop targeted campaigns with clear messaging and call-to-action

• Utilize data analytics to track campaign performance and make adjustments as needed

• Collaborate with sales team to ensure alignment and provide necessary support

• Regularly review and update marketing strategies based on ma...read more

Use SQL query to find the top 2 highest salaries in a table.

• Use the ORDER BY clause to sort the salaries in descending order.

• Use the LIMIT clause to limit the results to 2.

• Example: SELECT salary FROM employees ORDER BY salary DESC LIMIT 2;

To write power base 10 in logical coding, you can simply use the exponentiation operator or function.

• Use the exponentiation operator '**' in Python to calculate power base 10.

• In JavaScript, you can use the Math.pow() function to calculate power base 10.

• In Java, you can use the Math.pow() function as well to calculate power base 10.

Women's education is crucial for the development of society and the empowerment of women.

• Women's education leads to better health outcomes for themselves and their families.

• Educated women are more likely to participate in the workforce and contribute to the economy.

• Education can help women gain the skills and knowledge needed to advocate for their rights and challenge gender inequality.

• Investing in women's education has been shown to have a positive impact on reducing poverty...read more

I approach problem solving by breaking down the issue, analyzing possible solutions, and implementing the best course of action.

• Identify the problem and gather relevant information

• Brainstorm potential solutions

• Evaluate each solution based on feasibility and effectiveness

• Implement the chosen solution and monitor outcomes

• Adjust the approach if needed

Design Walmart search API

• Define search parameters (e.g. product name, category, price range)

• Implement search algorithm (e.g. keyword matching, relevance ranking)

• Integrate with Walmart's product database

• Provide filtering and sorting options

• Ensure scalability and performance

• Include error handling and logging