### findLexSmallestString 
from collections import deque
from typing import *
def f_gold(s: str, a: int, b: int) -> str:
    q = deque([s])
    vis = {s}
    ans = s
    while q:
        s = q.popleft()
        if s < ans:
            ans = s
        nxt1 = ''.join(
            [str((int(c) + a) % 10) if i & 1 else c for i, c in enumerate(s)]
        )
        nxt2 = s[-b:] + s[:-b]
        for nxt in (nxt1, nxt2):
            if nxt not in vis:
                vis.add(nxt)
                q.append(nxt)
    return ans