20+ NatWest Group Interview Questions and Answers

Q1. Problem Statement: Largest Subarray with Equal Number of 0s and 1s

Given an array containing only 0s and 1s, determine the length of the longest contiguous subarray that has an equal number of 0s and 1s.

Input:...read more

Q2. Maximum Sum of Two Non-Overlapping Subarrays

Given an integer array ARR and a positive integer K, your objective is to find two non-overlapping subarrays (contiguous) of length K each, such that their summed to...read more

Q3. Knight Probability in Chessboard

Calculate the probability that a knight remains on an N x N chessboard after making K moves. Initially, the knight is placed at a given position on the board. It can move in any...read more

Q4. Cycle Detection in a Singly Linked List

Determine if a given singly linked list of integers forms a cycle or not.

A cycle in a linked list occurs when a node's next points back to a previous node in the list. T...read more

Q5. Gas Tank Problem Statement

You have a car with a gas tank of infinite capacity. There are 'N' gas stations located along a circular route, numbered from 0 to N-1. You begin your journey with an empty tank from ...read more

Q6. Remove Character from String Problem Statement

Given a string str and a character 'X', develop a function to eliminate all instances of 'X' from str and return the resulting string.

Input:

The first line contai...read more

Q7. String Rearrangement Problem Statement

You are given a string of lowercase characters. The objective is to rearrange (reorder) the string so that no two adjacent characters are identical.

Return the rearranged ...read more

Q8. LRU Cache Design Question

Design a data structure for a Least Recently Used (LRU) cache that supports the following operations:

1. get(key) - Return the value of the key if it exists in the cache; otherwise, re...read more

Q9. Anagram Difference Problem Statement

Given two strings, 'STR1' and 'STR2', of equal lengths, determine the minimum number of manipulations required to make the two strings anagrams of each other.

Input:

The fir...read more

Q10. Binary Tree to Doubly Linked List

Transform a given Binary Tree into a Doubly Linked List.

Ensure that the nodes in the Doubly Linked List follow the Inorder Traversal of the Binary Tree.

Input:

The first line ...read more

Q11. Find Duplicates in an Array

Given an array ARR of size 'N', where each integer is in the range from 0 to N - 1, identify all elements that appear more than once.

Return the duplicate elements in any order. If n...read more

Q12. Count Nodes within K-Distance Problem Statement

Given a connected, undirected, and acyclic graph where some nodes are marked and a positive integer 'K'. Your task is to return the count of nodes such that the d...read more

Q13. Problem: Deletion in Circular Linked List

You are provided with a Circular Linked List of integers and a specific integer, referred to as 'key'.

Your task is to implement a function that locates the specified k...read more

Q14. Page Faults Identification Problem Statement

In computing, a page fault occurs when a process accesses a memory page that is not currently mapped by the memory management unit. To handle new pages being brought...read more

Q15. Closest Sum Problem Statement

Given an array of integers ARR of size N and an integer target, find three integers in ARR such that their sum is closest to the target. If there are two closest sums, return the s...read more

Q16. Boundary Traversal of Binary Tree

Given a binary tree of integers, your task is to print the boundary nodes of this binary tree in an anti-clockwise direction starting from the root node.

Input:

The first line ...read more

Q17. Deletion in Circular Linked List Problem Statement

Given a Circular Singly Linked List of integers, and a specific value 'VAL', your task is to delete the first occurrence of this value in the linked list. If t...read more

Q18. Can you explain how the file system is stored on a disk and how it works?

Q19. Given a problem statement and a code, how would you find and correct the bugs in the code?