Recursion

ProblemGiven a string s representing a valid expression, implement a basic calculator to evaluate it, and return the result of the evaluation. Note: You are not allowed to use any built-in function which evaluates strings as mathematical expressions, such as eval(). Example 1: 123Input: s = "1 + 1"Output: 2 Example 2: 123Input: s = " 2-1 + 2 "Output: 3 Example 3: 123Input: s = "(1+(4+5+2)-3)+(6+8)"Output: 23 Constraints: 1 <= s.length <= 3 * 10^5 s consist ...