Problem There is an exam room with n seats in a single row labeled from 0 to n - 1. When a student enters the room, they must...

Problem In this problem, a tree is an undirected graph that is connected and has no cycles. You are given a graph that starte...

Problem There is a strange printer with the following two special requirements: On each turn, the printer will print a solid...

Problem You are given a 0-indexed array heights of positive integers, where heights[i] represents the height of the iᵗʰ build...

Problem There is a strange printer with the following two special properties: The printer can only print a sequence of the s...

Problem The power of an integer x is defined as the number of steps needed to transform x into 1 using the following steps: ...

Problem You are given an array points, an integer angle, and your location, where location = [pos_x, pos_y] and points[i] = [...

Problem Given the root of a binary tree, return the postorder traversal of its nodes’ values. https://leetcode.com/problems/b...

Problem There is an undirected tree with n nodes labeled from 0 to n - 1. You are given the integer n and a 2D integer array ...

Problem Given an integer n, return all the structurally unique BST’s (binary search trees), which has exactly n nodes of uniq...

Problem There is a class with m students and n exams. You are given a 0-indexed m x n integer matrix score, where each row re...

Problem Given an integer n, return the number of structurally unique BST’s (binary search trees) which has exactly n nodes of...

Problem An n-bit gray code sequence is a sequence of 2ⁿ integers where: Every integer is in the inclusive range [0, 2ⁿ - 1],...

Problem Given two strings word1 and word2, return the minimum number of operations required to convert word1 to word2. You ha...

Problem Implement pow(x, n), which calculates x raised to the power n (i.e., xⁿ). https://leetcode.com/problems/powx-n/ Examp...

Problem Given an expression such as expression = "e + 8 - a + 5" and an evaluation map such as {"e":...

Problem Given a string s which represents an expression, evaluate this expression and return its value. The integer division ...

Problem Given a string s representing a valid expression, implement a basic calculator to evaluate it, and return the result ...

Problem Given the root of a perfect binary tree, reverse the node values at each odd level of the tree. For example, suppose...

Problem You are given a string s, which is known to be a concatenation of anagrams of some string t. Return the minimum possi...

Problem The thief has found himself a new place for his thievery again. There is only one entrance to this area, called root....

Problem Given two non-negative integers num1 and num2 represented as strings, return the product of num1 and num2, also repre...

Problem You are given a string s. A string t is called good if all characters of t occur the same number of times. You can pe...

Problem You are given an integer array arr of length n that represents a permutation of the integers in the range [0, n - 1]....

Problem There are n mountains in a row, and each mountain has a height. You are given an integer array height where height[i]...

Problem You are given an array prices where prices[i] is the price of a given stock on the iᵗʰ day, and an integer fee repres...

Problem You are given an array prices where prices[i] is the price of a given stock on the iᵗʰ day. Find the maximum profit y...

Problem You are given an integer array prices where prices[i] is the price of a given stock on the iᵗʰ day, and an integer k....

Problem Given an array of integers temperatures represents the daily temperatures, return an array answer such that answer[i]...

Problem Given a circular integer array nums (i.e., the next element of nums[nums.length - 1] is nums[0]), return the next gre...

Problem The next greater element of some element x in an array is the first greater element that is to the right of x in the ...

Problem You are given an integer array prices where prices[i] is the price of the iᵗʰ item in a shop. There is a special disc...