Haribhakti & Co Interview Questions and Answers

Sort an array of 0s, 1s, and 2s in linear time with a single scan approach.

• Use three pointers to keep track of the positions of 0s, 1s, and 2s in the array.

• Iterate through the array once and swap elements based on their values and the pointers.

• After the single scan, the array will be sorted in place with 0s, 1s, and 2s in order.

Find the fourth largest element in an array, return -2147483648 if not enough distinct elements.

• Sort the array in descending order

• Return the fourth element if it exists, else return -2147483648

Check if a node with a given value exists in a binary tree.

• Traverse the binary tree using depth-first search (DFS) or breadth-first search (BFS) to search for the node with the given value.

• Use a recursive or iterative approach to implement the search algorithm.

• Return 'true' if the node with the given value is found, otherwise return 'false'.

Find the shortest path in an unweighted graph from house 'S' to house 'T'.

• Use Breadth First Search (BFS) algorithm to find the shortest path in an unweighted graph.

• Create a queue to store the current house and its neighbors, and a visited set to keep track of visited houses.

• Start BFS from house 'S' and stop when reaching house 'T'.

• Return the path from 'S' to 'T' once 'T' is reached.

• If multiple shortest paths exist, return any one of them.

Remove duplicates from an array while maintaining order.

• Use a set to keep track of unique elements.

• Iterate through the array and add elements to the set if not already present.

• Convert the set back to an array to maintain order.

SQL joins are used to combine rows from two or more tables based on a related column between them.

• Inner Join: Returns rows when there is at least one match in both tables.

• Left Join: Returns all rows from the left table and the matched rows from the right table.

• Right Join: Returns all rows from the right table and the matched rows from the left table.

• Full Outer Join: Returns rows when there is a match in one of the tables.

• Cross Join: Returns the Cartesian product of the two ta...read more

Decorator in Python is a design pattern that allows adding new functionality to an existing object without modifying its structure.

• Decorators are functions that take another function as an argument and extend its behavior without explicitly modifying it.

• They are commonly used to add logging, timing, caching, or authentication to functions.

• Syntax for using decorators in Python involves using the @ symbol followed by the decorator function name above the function definition.

• Exa...read more

yield is a keyword in Python used in generator functions to return a value without terminating the function

• yield is used in generator functions to produce a series of values over time

• When a generator function is called, it returns an iterator object but does not start execution immediately

• Each time the yield statement is reached, the function's state is saved, and the value is returned to the caller

• Execution of the function is paused until the next call to the generator's __n...read more