algorithm collections
Algorithm
2196. Create Binary Tree From Descriptions #Hash #Binary tree problem You are given a 2D integer array descriptions where descriptions[i] = [parenti, childi, isLefti] indicates that parenti is the parent of childi in a binary tree of unique values. Furthermore, If isLefti == 1, then childi is the left child of
Algorithm
1823. Find the Winner of the Circular Game #Array #Math #Recursion #Queue #Simulation problem There are n friends that are playing a game. The friends are sitting in a circle and are numbered from 1 to n in clockwise order. More formally, moving clockwise from the ith friend brings you
Algorithm
2285. Maximum Total Importance of Roads #Greedy #Graph #Sorting #Heap(Priority Queue) problem You are given an integer n denoting the number of cities in a country. The cities are numbered from 0 to n - 1. You are also given a 2D integer array roads where roads[i] = [ai,
![[Blind75] Best time to buy and sell stock](/content/images/size/w600/2024/05/1_3N6z7wCvSkDRv_Kr1ZIk4A@2x-1-.jpeg)
Algorithm
121. Best Time to Buy and Sell Stock #Array #Dynamic Programming #blind75/2 problem You are given an array prices where prices[i] is the price of a given stock on the ith day. You want to maximize your profit by choosing a single day to buy one stock and
Algorithm
1. Two Sum #Array #Hash_table #blind75/1 problem Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target. You may assume that each input would have exactly one solution, and you may not use the same
Algorithm
2073. Time Needed to Buy Tickets #Easy #Queue problem There are n people in a line queuing to buy tickets, where the 0th person is at the front of the line and the (n - 1)th person is at the back of the line. You are given a 0-indexed
Algorithm
1700. Number of Students Unable to Eat Lunch #Easy #Queue problem The school cafeteria offers circular and square sandwiches at lunch break, referred to by numbers 0 and 1 respectively. All students stand in a queue. Each student either prefers square or circular sandwiches. The number of sandwiches in the
Algorithm
678. Valid Parenthesis String #Medium #stack #dp problem Given a string s containing only three types of characters: '(', ')' and '*', return true if s is valid. The following rules define a valid string: * Any left parenthesis '(' must have a corresponding right parenthesis '
Algorithm
1249. Minimum Remove to Make Valid Parentheses #Medium #stack problem Given a string s of '(' , ')' and lowercase English characters. Your task is to remove the minimum number of parentheses ('(' or ')', in any positions) so that the resulting parentheses string is valid and
Algorithm
1544. Make The String Great #Easy #Stack problem Given a string s of lower and upper case English letters. A good string is a string which doesn't have two adjacent characters s[i] and s[i + 1] where: * 0 <= i <= s.length - 2 * s[i]
Algorithm
1614. Maximum Nesting Depth of the Parentheses #Easy #Stack problem A string is a valid parentheses string (denoted VPS) if it meets one of the following: * It is an empty string "", or a single character not equal to "(" or ")", * It can be written as
Algorithm
205. Isomorphic Strings #Hash_table #String problem Given two strings s and t, determine if they are isomorphic. Two strings s and t are isomorphic if the characters in s can be replaced to get t. All occurrences of a character must be replaced with another character while preserving the