10+ Tower Research Capital LLC Software Developer Interview Questions and Answers

Given a binary tree, a target node, and an integer K, find all nodes at distance K from the target node.

• Traverse the binary tree to find the target node.

• Use BFS to traverse the tree from the target node to nodes at distance K.

• Keep track of the distance while traversing the tree.

• Return the values of nodes at distance K in any order.

Find the shortest path between two houses in a city represented as an unweighted graph.

• Use breadth-first search (BFS) algorithm to find the shortest path in an unweighted graph.

• Start BFS from the source house and keep track of the path taken to reach each house.

• Once the destination house is reached, backtrack from destination to source to find the shortest path.

• Consider using a queue data structure to implement BFS efficiently.

• Handle cases where multiple shortest paths exist ...read more

Calculate the minimum number of steps Ninja needs to cut down all trees in a forest grid.

• Iterate through the grid to find the shortest path to cut down all trees in order.

• Use a priority queue to keep track of the shortest trees to cut next.

• If it's impossible to cut all trees, return -1.

• Consider all four cardinal directions for movement in the grid.

Return all distinct palindromic substrings of a given string in alphabetical order.

• Iterate through all possible substrings of the given string.

• Check if each substring is a palindrome by comparing it with its reverse.

• Store all palindromic substrings in a set to ensure uniqueness.

• Return the sorted list of palindromic substrings.

Rearrange array numbers to form the largest possible numerical value by combining digits of each number in the array.

• Convert integers in the array to strings for easier manipulation.

• Sort the array of strings in non-increasing order based on custom comparison function.

• Join the sorted strings to form the largest possible number.

Check if two nodes in a binary tree are cousins by comparing their levels and parents.

• Traverse the tree to find the levels and parents of the given nodes.

• Compare the levels and parents of the two nodes to determine if they are cousins.

• If the levels are the same and the parents are different, the nodes are cousins.

Count the total number of nodes in a complete binary tree given its root.

• Traverse the tree in level order and count the nodes

• Use a queue to keep track of nodes at each level

• Check for null nodes represented by -1 in the input

• The total number of nodes in the example tree is 7

Find the length of the largest subarray with equal number of 0s and 1s in a given array.

• Iterate through the array and maintain a count of 0s and 1s encountered so far.

• Store the count difference in a hashmap with the index as the key.

• If the same count difference is encountered again, the subarray between the two indices has equal 0s and 1s.

• Return the length of the longest subarray found.

Calculate the perimeter of an island represented by a binary grid.

• Iterate through the grid and count the perimeter based on land cells and their adjacent cells.

• Each land cell contributes 4 units to the perimeter, subtract 2 units for each adjacent land cell.

• Handle edge cases where land cells are at the boundaries of the grid.

• Return the total perimeter for each test case.

ACID properties ensure database transactions are processed reliably. Rollback mechanism undoes changes if transaction fails.

• ACID properties: Atomicity, Consistency, Isolation, Durability

• Atomicity ensures all operations in a transaction are completed successfully or none at all

• Consistency ensures database remains in a valid state before and after transaction

• Isolation ensures transactions are independent and do not interfere with each other

• Durability ensures changes made by com...read more

To find and correct a bug in code, analyze problem statement, review code, use debugging tools, and test different scenarios.

• Understand the problem statement and expected output.

• Review the code for syntax errors, logical errors, and potential bugs.

• Use debugging tools like breakpoints, print statements, and IDE debuggers.

• Test the code with different inputs to identify the bug.

• Make necessary corrections based on the identified bug.

• Re-test the code to ensure the bug is fixed.