3216. Lexicographically Smallest String After a Swap

Given a string s containing only digits, return the lexicographically smallest string that can be obtained after swapping adjacent digits in s with the same parity at most once. Digits have the same parity if both are odd or both are even. For example, 5 and 9, as well as 2 and 4, have the same parity, while 6 and 9 do not. Example 1: Input: s = "45320" Output: "43520" Explanation: s[1] ==