Directi Software Developer Interview Questions and Answers

Identify duplicate elements in an array of integers within the range from 0 to N - 1.

• Iterate through the array and keep track of seen elements using a hash set.

• If an element is already in the set, it is a duplicate and can be added to the result.

• Return the list of duplicate elements found in the array.

• Example: For input [1, 3, 1, 3, 4], output should be ['1', '3'].

Implement a function to retrieve leaf nodes from a binary tree in left-to-right order.

• Traverse the binary tree in a depth-first manner, keeping track of leaf nodes encountered.

• Store leaf nodes in a list while traversing the tree.

• If leaf nodes are equidistant from the leftmost node, prefer the node at a lesser depth.

• Return the list of leaf nodes in the order they appear from left to right.

Dijkstra's algorithm is used to find the shortest path distance from a source node to all other nodes in a graph.

• Implement Dijkstra's algorithm to find the shortest path distances from node 0 to all other nodes in the graph.

• Use a priority queue to efficiently select the next node with the shortest distance.

• Initialize distances to all nodes as infinity except for the source node which is 0.

• Update distances to neighboring nodes if a shorter path is found.

• Repeat the process unti...read more

Calculate exclusive time of functions based on logs of function start and end times.

• Parse the input logs to calculate exclusive time for each function ID.

• Use a stack to keep track of function start times and calculate exclusive time when function ends.

• Iterate through the logs and update exclusive time for each function ID accordingly.

The task is to stack different types of rectangular 3D boxes to achieve the maximum possible height.

• Iterate through all possible rotations of each box type.

• Sort the boxes based on their base dimensions in non-increasing order.

• Use dynamic programming to find the maximum height achievable by stacking the boxes.

• Consider the constraints while implementing the solution.

• Example: For input [3, [4, 1, 4], [6, 2, 5], [7, 3, 6]], the output should be 15.

The task is to find all distinct triplets in an array that sum up to a given integer.

• Iterate through the array and use a nested loop to find all possible triplets.

• Use a set to store unique triplets and avoid duplicates.

• Check if the sum of the triplet equals the target sum.

• Return the list of valid triplets or -1 if no such triplet exists.

Given an array of stock prices, find the maximum profit from a single buy and sell action.

• Iterate through the array and keep track of the minimum price seen so far and the maximum profit achievable.

• Calculate the profit by subtracting the current price from the minimum price seen so far.

• If the profit is negative, set it to 0 as we can't sell without buying first.

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

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

• Initialize two variables: max_sum and current_sum to track the maximum sum subarray

• Iterate through the array and update current_sum by adding the current element or starting a new subarray

• Update max_sum if current_sum becomes greater than max_sum