Given a string s containing only three types of characters: ‘(‘, ‘)’ and ‘*’, return true if s is&nb…
My memo and playground
My memo and playground
Given a string s containing only three types of characters: ‘(‘, ‘)’ and ‘*’, return true if s is&nb…
Given a string s of ‘(‘ , ‘)’ and lowercase English characters. Your task is to remove the minimum number of parentheses…
Given a string s of lower and upper case English letters. A good string is a string which doesn’t have two adjacent characters&nb…
A string is a valid parentheses string (denoted VPS) if and only if it consists of “(” and “)” characters only, and: We …
A string is a valid parentheses string (denoted VPS) if it meets one of the following: We can similarly define the nesting depth&n…
Given a string s representing a valid expression, implement a basic calculator to evaluate it, and return the result of the evaluation.…
You are given an array of strings tokens that represents an arithmetic expression in a Reverse Polish Notation. Evaluate the expression…
Design a stack that supports push, pop, top, and retrieving the minimum element in constant time. Implement the MinStack class: You must imp…
Given a string path, which is an absolute path (starting with a slash ‘/’) to a file or directory in a Unix-style file system, con…
Given a string s containing just the characters ‘(‘, ‘)’, ‘{‘, ‘}’, ‘[‘ and ‘]’, determine if the input s…