10+ HashedIn by Deloitte Software Engineer Interview Questions and Answers

Check if two binary trees are mirrors of each other based on specific criteria.

• Compare the roots of both trees.

• Check if the left subtree of the first tree is the mirror of the right subtree of the second tree.

• Verify if the right subtree of the first tree is the mirror of the left subtree of the second tree.

The problem involves finding the number of distinct ways to climb N stairs by taking 1 or 2 steps at a time.

• Use dynamic programming to solve the problem efficiently.

• The number of ways to reach the Nth stair is the sum of the number of ways to reach the (N-1)th stair and the (N-2)th stair.

• Handle base cases for N=0 and N=1 separately.

• Consider using modulo operation to avoid overflow for large values of N.

Design a 2-player Tic-Tac-Toe game on an N x N grid where players place their marks to win by getting N marks in a row.

• Create a 2D array to represent the game board.

• Implement a function to check for a win after each move.

• Handle player moves and update the board accordingly.

• Return the result of each move (0, 1, or 2) based on the game state.

• Consider horizontal, vertical, and diagonal win conditions.

Given an array representing digits of a number, add 1 to the number.

• Iterate through the array from right to left, starting with the least significant digit.

• Add 1 to the current digit and check if it becomes 10. If so, set it to 0 and carry over to the next digit.

• Handle the case where the most significant digit needs to be incremented by creating a new array with an extra digit.

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

• Create a dynamic programming table to store the number of ways to make change for each value up to the target value.

• Iterate through each denomination and update the table accordingly based on the current denomination.

• The final value in the table will represent the total number of ways to make change for the target value.

• Consider edge cases such as when the target v...read more

Convert Excel column title to corresponding column number.

• Iterate through each character in the input string

• Calculate the corresponding value of each character based on its position in the alphabet

• Multiply the value by 26 raised to the power of its position from the right in the input string

• Sum up all the values to get the final column number

Q1 - Pre order traversal without recursion. Q2 - Reverse a linked list.

• Q1: Use a stack to keep track of nodes. Start with root, push it to stack. Pop top node, print it, push right and left children to stack.

• Q2: Traverse the linked list and change the direction of the pointers. Set the head of the reversed list as the last node of the original list.

Sort a string based on the frequency of its characters.

• Create a hash table to store the frequency of each character.

• Sort the characters based on their frequency using a sorting algorithm.

• Reconstruct the string based on the sorted characters and their frequency.

Sharding is a database partitioning technique to improve performance and scalability.

• It involves dividing a large database into smaller, more manageable parts called shards.

• Each shard contains a subset of the data and can be stored on a separate server.

• Sharding can be implemented using different strategies such as range-based, hash-based, or round-robin.

• It requires careful planning and coordination to ensure data consistency and availability.

• Examples of sharding in popular da...read more

Asymptotic notation is a way to describe the performance of an algorithm in terms of its input size.

• Asymptotic notation is used to analyze the efficiency of algorithms by focusing on how they behave as the input size approaches infinity.

• Common notations include O (Big O), Ω (Big Omega), and Θ (Big Theta), which represent the worst-case, best-case, and average-case time complexity respectively.

• For example, if an algorithm has a time complexity of O(n^2), it means that the algo...read more

Design a system for parking management

• Use sensors to detect available parking spots

• Implement a payment system for parking fees

• Include a mobile app for users to find and reserve parking spots

• Utilize cameras for security monitoring

• Integrate with navigation apps for real-time parking availability updates