import sys
from math import pi

from typing import List, Tuple

int1 = lambda x: int(x) - 1
input = lambda: sys.stdin.readline().rstrip('\n')
ii = lambda: int(input())
vi = lambda: list(map(int, input().split()))
vi1 = lambda: list(map(int1, input().split()))


def dbg(*args, **kwargs):
    print(*(repr(arg) for arg in args), *(f'{k}: {repr(v)}' for k, v in kwargs.items()),
          sep='; ', file=sys.stderr, flush=True)


def main():
    n, q = vi()
    s = list(input())
    for _ in range(q):
        x, *re = input().split()
        if x == '1':
            i, c = re
            s[int(i) - 1] = c
        else:
            t = re[0]
            try:
                cur = 0
                for c in t:
                    cur = s.index(c, cur) + 1
                print('Yes')
            except:
                print('No')


def _start():
    if (ret := main()) is not None:
        print(*ret) if isinstance(ret, List) or isinstance(ret, Tuple) else print(ret)


if __name__ == '__main__':
    _start()