Software Engineer, new Grad Interview Questions and Answers

Determining the state of switches/junctions after N trains have passed through them.

• Create an array to represent the state of each switch/junction

• Iterate through each train and update the state of the corresponding switch/junction

• Use a loop to simulate the passing of trains and updating of switches/junctions

• Return the final state of the switches/junctions

A program to solve the 15-Puzzle by rearranging tiles into the correct order using an empty space.

• The 15-Puzzle consists of a 4x4 grid with 15 numbered tiles and one empty space.

• The goal is to arrange the tiles in ascending order from 1 to 15, with the empty space at the bottom right.

• Use algorithms like A* or BFS for finding the solution efficiently.

• Example initial state: [[12, 2, 3, 4], [10, 6, 7, 1], [9, 11, 5, 13], [8, 14, 15, '']].

• Example goal state: [[1, 2, 3, 4], [5, 6,...read more

Level order traversal of a binary search tree (BST) is a breadth-first search algorithm that visits each level of the tree from left to right.

• Use a queue to keep track of the nodes to be visited

• Start with the root node and enqueue it

• While the queue is not empty, dequeue a node and visit it

• Enqueue the left and right child of the visited node if they exist

• Repeat until all nodes have been visited

Move all zeros to the end of the array while maintaining the relative order of the non-zero elements.

• Iterate through the array and keep track of the index to place the next non-zero element.

• When encountering a non-zero element, swap it with the element at the current index.

• After iterating through the array, all zeros will be moved to the end while maintaining the order of non-zero elements.

Count the number of islands in a grid, where an island is a group of connected 1s.

• Use depth-first search (DFS) or breadth-first search (BFS) to traverse the grid

• For each cell with a 1, mark it as visited and explore its neighboring cells

• Count the number of times you start a new DFS or BFS traversal