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Get StartedGiven a mobile keypad having digits from 0 to 9 associated with each key, count total possible combinations of digits having length n. We can start with any digit and press only four adjacent keys of any digit. The keypad also contains * and # keys, which we are not allowed to press.
Given a string, break it into all possible combinations of non-overlapping substrings enclosed within curly brackets.
Given a positive integer, find the minimum number possible by doing at-most k swap operations upon its digits.
The Longest Common Subsequence (LCS) problem is finding the longest subsequence present in given two sequences in the same order, i.e., find the longest sequence which can be obtained from the first original sequence by deleting some items and from the second original sequence by deleting other items.
Given a directed graph, check if it is strongly connected or not. A directed graph is said to be strongly connected if every vertex is reachable from every other vertex.
Find all n–digit strictly increasing numbers where n varies from 1 to 9. If we process the number from left to right and every digit is greater than the preceding digit, we can say that the number is strictly increasing.
Given a binary tree, write an efficient algorithm to check if a tree is height-balanced or not. In a height-balanced tree, the absolute difference between the height of the left and right subtree for every node is 0 or 1.
Write an efficient program to convert a given number to words.
Lexicographic sorting: Given a set of strings, print them in lexicographic order (dictionary/alphabetical order).
Given a huge set of words with duplicates present, find the maximum occurring word in it. If two words have the same count, return any one of them.
This post covers memory-efficient implementation of Trie data structure in C++ using the map data structure. Trie is a tree-based data structure, which is used for efficient retrieval of a key in a large dataset of strings.
Given an M × N boggle board, find a list of all possible words that can be formed by a sequence of adjacent characters on the board.