Suppose we have a string containing digits from 2-9. We have to find all possible letter combinations that the number could generate. One mapping of digit to letters (just like on the telephone buttons) is given below. Note that 1 does map some characters but no letters.12a b c3d e ... Read More

Suppose we have a n x n matrix represents a chess board. There are some 1s and 0s, where 1 represents a queen and 0 represents an empty cell. We have to check whether the board is valid solution to the N-Queen puzzle or not. As we know a board ... Read More

Suppose we have a list of lists called rooms. Each index i in rooms represents a room and rooms[i] represents different keys to open other rooms. The room 0 is open and we are at that room and every other room is locked. We can move freely between opened rooms; ... Read More

Suppose we have a number n; we have to find the nth ugly number. As we know that the ugly numbers are those numbers, whose prime factors are only 2, 3 and 5. So if we want to find 10th ugly number, the output will be 12, as the first ... Read More

Suppose we have a list of numbers called nums. And it is representing the height of square blocks, we have to check whether the shape is symmetric over the y = x line or not.So, if the input is like nums = [7, 5, 3, 2, 2, 1, 1], then ... Read More

Suppose we have a linked list. We have to sort the list into ascending order.So, if the input is like [5, 8, 4, 1, 5, 6, 3], then the output will be [1, 3, 4, 5, 5, 6, 8, ]To solve this, we will follow these steps:values := a new ... Read More

Suppose we have a list of numbers called items and another value n. A salesman has items in a bag with random IDs. The salesman can delete as many as n items from the bag. We have to find the minimum number of different IDs in the bag after n ... Read More

Suppose we have two binary trees; we have to check whether the sequence of leaves left-to-right in both trees are the same.So, if the input is likethen the output will be True as the sequence is [2, 6] for both trees.To solve this, we will follow these steps:c := a ... Read More

Suppose we have a string and a set of delimiters, we have to reverse the words in the string while the relative ordering of the delimiters should not be changed.So, if the input is like s = "Computer/Network:Internet|tutorialspoint" delims = ["/", ":", '|'], then the output will be tutorialspoint/Internet:Network|ComputerTo solve ... Read More

Suppose we have linked list, we also have two values i and j, we have to reverse the linked list from i to jth nodes. And finally return the updated list.So, if the input is like [1, 2, 3, 4, 5, 6, 7, 8, 9] i = 2 j = ... Read More