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Get StartedGiven an M × N matrix of characters, find the length of the longest path in the matrix starting from a given character. All characters in the longest path should be increasing and consecutive to each other in alphabetical order.
Given an unsorted integer array, find two non-overlapping pairs in it having the same sum.
Given an M × N binary matrix, replace all occurrences of 0’s by 1’s, which are completely surrounded by 1’s from all sides (top, left, bottom, right, top-left, top-right, bottom-left, and bottom-right).
Find the minimum number of moves required for converting an array of zeros to a given array using only increment and double operations. The increment operation increases the value of an array element by 1. And the double operation doubles the value of each array element.
Given a binary tree, write an efficient algorithm to print its right view. For example, the right view of a given binary tree is 1, 3, 6, 8.
Given two sorted linked lists, merge them without using extra space without modifying links of the first list. The solution should preserve the sorted order of elements in both lists.
Given a directed acyclic graph (DAG), print it in Topological order using Kahn’s topological sort algorithm. If the DAG has more than one topological ordering, print any of them.
Given two strings, determine if the first string can be transformed into the second string with a single edit operation. An edit operation can insert, remove, or replace a character in the first string.
Given an integer, swap adjacent bits of it. In other words, swap bits present at even positions with those present in odd positions.
Write an efficient algorithm to find postorder traversal on a given binary tree from its inorder and preorder sequence.
Given a BST and a valid range of keys, remove nodes from BST that have keys outside the valid range.
Given a sequence of n numbers such that the difference between the consecutive terms is constant, find the missing term in logarithmic time.