### minSwaps 
from typing import *
def f_gold(s: str) -> int:
    s0n0 = s0n1 = s1n0 = s1n1 = 0
    for i in range(len(s)):
        if (i & 1) == 0:
            if s[i] != '0':
                s0n0 += 1
            else:
                s1n1 += 1
        else:
            if s[i] != '0':
                s1n0 += 1
            else:
                s0n1 += 1
    if s0n0 != s0n1 and s1n0 != s1n1:
        return -1
    if s0n0 != s0n1:
        return s1n0
    if s1n0 != s1n1:
        return s0n0
    return min(s0n0, s1n0)