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
def main():
    from bisect import bisect_left,bisect
    n = int(input())
    s = list(input())
    q = int(input())
    al=[[] for i in range(26)]
    for i in range(n):
        al[ord(s[i])-97].append(i)
    ans = []
    for i in range(q):
        a , b , x = input().split()
        if a == "1":
            al[ord(s[int(b)-1])-97].pop(bisect_left(al[ord(s[int(b)-1])-97],int(b)-1))
            al[ord(x)-97].insert(bisect_left(al[ord(x)-97],int(b)-1),int(b)-1)
            s[int(b)-1] = x
        elif a == "2":
            b = int(b)-1
            x = int(x)-1
            cou = 0
            for j in range(26):
                l = bisect_left(al[j],b)
                r = bisect(al[j],x)
                if l != r:
                    cou += 1
            ans.append(cou)
    for i in ans:
        print(i)

if __name__ == '__main__':
    main()