LEETCODE 1249: PYTHON SOLUTION TO MIN REMOVE TO MAKE STRING VALID

LeetCode problem 1249, "Minimum Remove to Make Valid Parentheses," involves modifying a string to remove the minimum number of parentheses so that the resulting string is valid. A valid string has balanced parentheses, meaning every opening parenthesis `(` has a corresponding closing parenthesis `)`. The Python solution uses a stack to track the indices of unmatched opening parentheses and a set to record indices of invalid closing parentheses. After identifying all mismatches, the solution reconstructs the string by omitting characters at these invalid indices. This approach efficiently ensures the minimum number of removals for a valid string.