Patel Infrastructure Interview Questions and Answers

Finding number of paths in tree with sum of node values equal to count using recursion.

• Use recursion to traverse the tree and keep track of the sum of node values.

• At each node, check if the current sum equals the desired count.

• If yes, increment the path count.

• Recursively traverse the left and right subtrees.

• Return the total path count.

• Example: Given a tree with values [10, 5, -3, 3, 2, null, 11], count the number of paths with sum equal to 8.

• The answer would be 3, as there ar...read more

A graph data structure can be used to solve a Rubix cube.

• Each cubelet can be represented as a node in the graph.

• Edges can be added between nodes to represent possible moves.

• A search algorithm like BFS or DFS can be used to find the solution.

Stack data structure is suitable for implementing Redo and Undo operations.

• Stack follows Last-In-First-Out (LIFO) order, which is ideal for undoing and redoing operations.

• When an operation is performed, it can be pushed onto the stack for undoing later.

• To redo an operation, the previously undone operations can be popped from the stack.

• Stack provides efficient insertion and deletion at one end, making it suitable for undo and redo functionality.

Dynamic programming solution to find if a given weight can be formed using an array of weights

• Create a boolean array of size (given weight + 1) to store if a weight can be formed or not

• Initialize the first element of the boolean array to true

• Iterate through the array of weights and for each weight, iterate through the boolean array and mark true for all weights that can be formed using the current weight

• Return the value at the index of the given weight in the boolean array

A router is a networking device that forwards data packets between computer networks.

• Routers operate at the network layer of the OSI model.

• They use routing tables to determine the best path for data packets to travel.

• Routers can connect multiple networks together, such as a home network to the internet.

• They can also provide security by blocking unauthorized access to a network.

• Examples of routers include Cisco, Netgear, and TP-Link.

Arrange 8 queens on a chessboard so that no two queens threaten each other.

• Each queen must be placed in a different row and column

• No two queens can be in the same diagonal

• There are 92 possible solutions

• One solution is: (0, 4), (1, 2), (2, 7), (3, 3), (4, 6), (5, 1), (6, 5), (7, 0)

The internet is a global network of interconnected devices that communicate with each other using standardized protocols.

• The internet is made up of millions of interconnected devices such as computers, servers, routers, and switches.

• Data is transmitted across the internet using standardized protocols such as TCP/IP.

• The internet is accessed through Internet Service Providers (ISPs) who provide users with a connection to the internet.

• Websites are hosted on servers and accessed ...read more

Find subarray with given sum in an array of integers.

• Use a sliding window approach to find subarray with sum equal to given sum.

• Keep track of current sum and adjust window size accordingly.

• Return the indices of the subarray if found, else return an empty array.