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
#input = sys.stdin.buffer.readline
import bisect

def main():
    N = int(input())
    S = list(str(input()))
    
    pos = [[] for _ in range(26)]
    for x,s in enumerate(S):
        num = ord(s)-ord("a")
        pos[num].append(x)
    
    q = int(input())
    for _ in range(q):
        m,a,b = map(str,input().split())
        if m == "1":
            a = int(a)-1
            if S[a] == b:
                continue
            else:
                popind = bisect.bisect_left(pos[ord(S[a])-ord("a")],a)
                pos[ord(S[a])-ord("a")].pop(popind)
                bisect.insort(pos[ord(b)-ord("a")],a)
                S[a] = b
        else:
            a,b = int(a)-1,int(b)-1
            count = 0
            for i in range(26):
                l = bisect.bisect_left(pos[i],a)
                if l >= len(pos[i]):
                    continue
                if pos[i][l] <= b:
                    count += 1
            print(count)

if __name__ == "__main__":
    main()
