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
def input(): return sys.stdin.readline().rstrip()
from bisect import bisect_left,bisect
def main():
    n=int(input())
    S=list(input())
    q=int(input())
    set_s={chr(ord('a')+i):[] for i in range(26)}
    for i,s in enumerate(S):
        set_s[s].append(i)
    for _ in range(q):
        query=input().split()
        if query[0]=="1":
            i,c=int(query[1])-1,query[2]
            if S[i]==c:continue
            set_s[S[i]].remove(i)
            set_s[c].insert(bisect_left(set_s[c],i),i)
            S[i]=c
        else:
            l,r=int(query[1])-1,int(query[2])-1
            ans=0
            for i in range(26):
                ss=chr(ord('a')+i)
                if bisect(set_s[ss],r)>bisect_left(set_s[ss],l):
                    ans+=1
            print(ans)


if __name__=='__main__':
    main()