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():
    import sys
    input = sys.stdin.readline
    from bisect import bisect_left, insort_left
    N = int(input())
    S = list(input())
    Q = int(input())
    dic = {chr(i): [] for i in range(ord('a'), ord('z')+1)}
    for i in range(N):
        dic[S[i]].append(i)
    for _ in range(Q):
        query, a, c = input().split()
        if query == "1":
            i = int(a)-1
            if S[i] == c:
                continue
            ind = bisect_left(dic[S[i]], i)
            dic[S[i]].pop(ind)
            insort_left(dic[c], i)
            S[i] = c
        else:
            l, r = int(a)-1, int(c)-1
            ans = 0
            for inds in dic.values():
                if inds and l <= inds[-1] and inds[bisect_left(inds, l)] <= r:
                    ans += 1
            print(ans)

if __name__ == '__main__':
    main()