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Get StartedGiven two binary arrays, X and Y, find the length of the longest continuous sequence that starts and ends at the same index in both arrays and have the same sum. In other words, find max(j-i+1) for every j >= i, where the sum of subarray X[i, j] is equal to the sum of subarray Y[i, j]
Given an N × N ancestor matrix, whose cell (i, j) has the value true if i is the ancestor of j in a binary tree, construct a binary tree from it where binary tree nodes are labeled from 0 to N-1.
Write code to print all combinations of positive integers in increasing order that sum to a given positive number.
Given a string and a pattern, determine if the pattern matches with the string or not. The solution should not use any regex.
Write an efficient algorithm to check if a given string is k–palindrome or not. A string is k–palindrome if it becomes a palindrome on removing at most k characters from it.
The KMP Algorithm (or Knuth, Morris, and Pratt string searching algorithm) cleverly uses the previous comparison data. It can search for a pattern in linear time as it never re-compares a text symbol that has matched a pattern symbol.
Write an algorithm to replace each element in an array of positive integers such that the difference between adjacent elements in the array is less than or equal to a given target. The goal is to minimize the adjustment cost, which is the sum of differences between new and old values.
Huffman coding (also known as Huffman Encoding) is an algorithm for doing data compression, and it forms the basic idea behind file compression. This post talks about the fixed-length and variable-length encoding, uniquely decodable codes, prefix rules, and Huffman Tree construction.
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.
This post will discuss how to find permutations of a string using iteration. The implementation should be able to handle strings with duplicate characters and don’t repeat the permutations.
Write an efficient program to convert a given number to words.
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.