Problem Given an array of strings nums containing n unique binary strings each of length n, return a binary string of length ...

Problem You are given a positive integer n. Let even denote the number of even indices in the binary representation of n with...

Problem You are given an 0-indexed integer array prices where prices[i] denotes the number of coins needed to purchase the (i...

Problem A happy string is a string that: consists only of letters of the set ['a', 'b', 'c']. s[i] != s[i + 1] for all value...

Problem You are given m arrays, where each array is sorted in ascending order. You can pick up two integers from two differen...

Problem You are given a 0-indexed string pattern of length n consisting of the characters 'I' meaning increasing and 'D' mean...

Problem Design a data structure to find the frequency of a given value in a given subarray. The frequency of a value in a sub...

Problem You have n tiles, where each tile has one letter tiles[i] printed on it. Return the number of possible non-empty sequ...

Problem Given an integer array sorted in non-decreasing order, there is exactly one integer in the array that occurs more tha...

Problem Given an integer n, find a sequence that satisfies all of the following: The integer 1 occurs once in the sequence. ...

Problem Given an array arr, replace every element in that array with the greatest element among the elements to its right, an...

Problem Given a positive integer n, return the punishment number of n. The punishment number of n is defined as the sum of th...

Problem You have a 2-D grid of size m x n representing a box, and you have n balls. The box is open on the top and bottom sid...

Problem Design an algorithm that accepts a stream of integers and retrieves the product of the last k integers of the stream....

Problem In the universe Earth C-137, Rick discovered a special form of magnetic force between two balls if they are put in hi...

Problem You are working in a ball factory where you have n balls numbered from lowLimit up to highLimit inclusive (i.e., n ==...

Problem You are given a 0-indexed array nums consisting of positive integers. You can choose two indices i and j, such that i...

Problem A game is played by a cat and a mouse named Cat and Mouse. The environment is represented by a grid of size rows x co...

Problem Given two strings s and part, perform the following operation on s until all occurrences of the substring part are re...

Problem You are given a string s. Your task is to remove all digits by doing this operation repeatedly: Delete the first dig...

Problem You are given a 0-indexed integer array nums. A pair of indices (i, j) is a bad pair if i < j and j - i != nums[j]...

Problem Given an integer array nums sorted in non-decreasing order, remove some duplicates in-place such that each unique ele...

Problem Given an integer array nums sorted in non-decreasing order, remove the duplicates in-place such that each unique elem...

Problem Design a number container system that can do the following: Insert or Replace a number at the given index in the sys...

Problem You are given an m x n integer array grid. There is a robot initially located at the top-left corner (i.e., grid[0][0...

Problem You are given an integer limit and a 2D array queries of size n x 2. There are limit + 1 balls with distinct labels i...

Problem Given a positive integer n, generate an n x n matrix filled with elements from 1 to n² in spiral order. https://leetc...

Problem Given a collection of numbers, nums, that might contain duplicates, return all possible unique permutations in any or...

Problem Given an array nums of distinct positive integers, return the number of tuples (a, b, c, d) such that a * b = c * d w...

Problem Given an array nums of distinct integers, return all the possible permutations. You can return the answer in any orde...

Problem You are given two strings s1 and s2 of equal length. A string swap is an operation where you choose two indices in a ...

Problem Given an integer array nums that may contain duplicates, return all possible subsets (the power set). A subset of an...