10+ Cult.fit Software Developer Intern Interview Questions and Answers

Find the maximum sum of any contiguous subarray in an array of numbers in O(N) time.

• Use Kadane's algorithm to find the maximum subarray sum in O(N) time.

• Initialize two variables: max_sum and current_sum to keep track of the maximum sum found so far and the current sum of the subarray being considered.

• Iterate through the array and update current_sum by adding the current element or starting a new subarray if the current element is greater than the sum so far.

• Update max_sum if ...read more

Determine if a valid balanced sequence can be achieved by replacing 'X's with suitable brackets.

• Iterate through the string and keep track of the count of opening and closing brackets.

• If at any point the count of closing brackets exceeds the count of opening brackets, return False.

• If all 'X's can be replaced to form a valid balanced sequence, return True.

Merge overlapping intervals and return sorted list of merged intervals by start time.

• Sort the intervals based on start time.

• Iterate through intervals and merge overlapping intervals.

• Return the list of merged intervals sorted by start time.

Search for integers in a rotated sorted array efficiently using binary search.

• Use binary search to efficiently find the index of each query integer in the rotated sorted array.

• Handle the rotation of the array by finding the pivot point first.

• Check which half of the array the query integer falls into based on the pivot point.

• Return the index of the query integer if found, else return -1.

Given a list of strings, determine if a target string can be formed by combining one or more strings from the list.

• Iterate through all possible combinations of strings from the list to form the target string.

• Use recursion to try different combinations of strings.

• Check if the current combination forms the target string.

• Return true if a valid combination is found, otherwise return false.

Given a Balanced BST and a target integer, determine if there exists a pair of nodes with sum equal to the target.

• Traverse the BST in-order to get a sorted array of values.

• Use two pointers approach to find the pair with sum equal to target.

• Consider edge cases like negative numbers and duplicates.

• Time complexity can be optimized to O(n) using a HashSet to store visited nodes.

Compute the area of the largest rectangle that can be formed within the bounds of a given histogram.

• Iterate through the histogram bars and maintain a stack to keep track of increasing heights.

• Calculate the area of the rectangle by considering the current height and the width of the rectangle.

• Update the maximum area found so far as you iterate through the histogram.

• Handle edge cases like when the stack is empty or when the current height is less than the previous height.

The job scheduling problem involves maximizing profit by scheduling jobs with deadlines and profits optimally.

• Sort the jobs in decreasing order of profit.

• Iterate through the sorted jobs and schedule them based on their deadlines.

• Keep track of the maximum profit achievable by scheduling jobs within their deadlines.

• Example: For input Jobs: 'A'(profit=20, deadline=1), 'B'(profit=30, deadline=2), 'C'(profit=40, deadline=2), the maximum profit is 70 by scheduling 'C' at time 1 and...read more

The task is to minimize the cost of breaking a board into smaller squares by making horizontal and vertical cuts.

• Iterate through all possible horizontal and vertical cuts to find the minimum cost

• Use dynamic programming to optimize the solution by storing intermediate results

• Calculate the total cost by summing up the costs of all cuts

Return the boundary nodes of a binary tree in Anti-Clockwise direction starting from the root node.

• Traverse the left boundary nodes in top-down order

• Traverse the leaf nodes in left-right order

• Traverse the right boundary nodes in bottom-up order

• Handle duplicates by including them only once

Given a matrix representing water heights, find coordinates where water can flow to both Pacific and Atlantic oceans.

• Create a function that performs a depth-first search to find coordinates where water can flow to both oceans.

• Keep track of visited cells and check if a cell can flow to both oceans by comparing its height with neighboring cells.

• Return the coordinates in lexicographical order as the output.

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

• Use a circular linked list to simulate the circle of people.

• Iterate through the list, skipping K-1 nodes and removing the Kth node until only one node remains.

• Return the position of the last remaining node.

• Example: For N=5, K=2, the last person standing is at position 3.