from sortedcontainers import SortedSet

N,Q=map(int,input().split())
idx=[SortedSet() for i in range(26)]
S=input()
for i in range(N):
    idx[ord(S[i])-97].add(i)

ans=[]
for _ in range(Q):
    q=list(input().split())
    if q[0]=='1':
        i,c=q[1:]
        i=int(i)-1
        idx[ord(S[i])-97].remove(i)
        idx[ord(c)-97].add(i)

    else:
        cur=-1
        ok=True
        t=q[1]
        for i in range(len(t)):
            if not idx[ord(t[i])-97]:
                ok=False
                break
            nx=idx[ord(t[i])-97].bisect_right(cur)
            if nx==len(idx[ord(t[i])-97]):
                ok=False
                break
            cur=idx[ord(t[i])-97][nx]
        ans.append("Yes" if ok else 'No')

import sys
sys.stdout.write('\n'.join(map(str,ans))+'\n')