You are given a string S of length N consisting of lowercase English letters.

Process Q queries of the following two types:

* Type 1: change the i_q-th character of S to c_q. (Do nothing if the i_q-th character is already c_q.)
* Type 2: answer the number of different characters occurring in the substring of S between the l_q-th and r_q-th characters (inclusive).

Constraints

* N, Q, i_q, l_q, and r_q are integers.
* S is a string consisting of lowercase English letters.
* c_q is a lowercase English letter.
* 1 \leq N \leq 500000
* 1 \leq Q \leq 20000
* |S| = N
* 1 \leq i_q \leq N
* 1 \leq l_q \leq r_q \leq N
* There is at least one query of type 2 in each testcase.

Input

Input is given from Standard Input in the following format:


N
S
Q
Query_1
\vdots
Query_Q


Here, Query_i in the 4-th through (Q+3)-th lines is one of the following:


1 i_q c_q



2 l_q r_q


Output

For each query of type 2, print a line containing the answer.

Example

Input

7
abcdbbd
6
2 3 6
1 5 z
2 1 1
1 4 a
1 7 d
2 1 7


Output

3
1
5
import sys
from bisect import bisect_left,bisect_right,insort
#input = sys.stdin.readline

def main():
    n=int(input())
    s=list(str(input()))
    p=[[] for _ in range(26)]
    for i,S in enumerate(s):
        p[ord(S)-ord('a')].append(i)
    q=int(input())
    for i in range(q):
        a,b,c=map(str,input().split())
        if a=='1':
            b=int(b)-1
            if s[b]==c:
                continue
            else:
                insl=bisect_left(p[ord(s[b])-ord('a')],b)
                p[ord(s[b])-ord('a')].pop(insl)
                insort(p[ord(c)-ord('a')],b)
                s[b]=c
        else:
            b,c=int(b)-1,int(c)-1
            cnt=0
            for i in range(26):
                insl=bisect_left(p[i],b)
                if insl>=len(p[i]):
                    continue
                elif p[i][insl]<=c:
                    cnt+=1
            print(cnt)

if __name__ == '__main__':
    main()