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Given two strings s and t, return true if they are equal when both are typed into empty text editors.

You are given a string s.

A file system keeps a log each time some user performs a change folder operation.

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

Given a string s of lower and upper case English letters.

Given a valid parentheses string s, return the nesting depth of s.

You are given a string s consisting only of uppercase English letters.

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 same array.

The school cafeteria offers circular and square sandwiches at lunch break, referred to by numbers 0 and 1 respectively.

You are given a string s consisting of lowercase English letters.

A valid parentheses string is either empty "", "(" + A + ")", or A + B, where A and B are valid parentheses strings, and + represents string concatenation.

Given a 0-indexed string word and a character ch, reverse the segment of word that starts at index 0 and ends at the index of the first occurrence of ch (inclusive).

Determine if a string of brackets is properly matched and nested.

Given an array of n integers nums, a 132 pattern is a subsequence of three integers nums[i], nums[j] and nums[k] such that i < j < k and nums[i] < nums[k] < nums[j].

We are given an array asteroids of integers representing asteroids in a row.

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

You are given an array heights of n integers representing the number of bricks in n consecutive towers.

You are given a 0-indexed array maxHeights of n integers.

You are given an integer array target and an integer n.

There are n cars at given miles away from the starting mile 0, traveling to reach the mile target.

A parentheses string is a non-empty string consisting only of '(' and ')'.

Given a string s, determine if it is valid.

The factorial of a positive integer n is the product of all positive integers less than or equal to n.

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

There are n cars on an infinitely long road.

Given an m x n binary matrix mat, return the number of submatrices that have all ones.

Given an array of integers temperatures represents the daily temperatures, return an array answer such that answer[i] is the number of days you have to wait after the ith day to...

Given an encoded string, return its decoded string.

You are given an encoded string s.

You are given an array of strings tokens that represents an arithmetic expression in a Reverse Polish Notation.

On a single-threaded CPU, we execute a program containing n functions.

You are given a string s.

Given an integer array nums and a positive integer k, return the most competitive subsequence of nums of size k.

You are given a string s.

Suppose we have a file system that stores both files and directories.

We are given hours, a list of the number of hours worked per day for a given employee.

You are given an integer array nums.

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

A string is a valid parentheses string (denoted VPS) if and only if it consists of "(" and ")" characters only, and: We can similarly define the nesting depth depth(S) of any VPS...

You are given a string s and two integers x and y.