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
import bisect
input = sys.stdin.readline
sys.setrecursionlimit(10**6)


def main():

    n = int(input())
    s = list(input().strip())
    q = int(input())
    alpha = g = [[] for _ in range(26)]
    orda = ord('a')
    for i in range(n):
        alpha[ord(s[i])-orda].append(i)
    for i in range(q):
        a, b, c = map(str, input().split())
        if a == '1':
            b = int(b)-1
            if c != s[b]:
                alpha[ord(s[b])-orda].remove(b)
                s[b] = c
                bisect.insort(alpha[ord(c)-orda], b)
        else:
            ans = 0
            for i in range(26):
                if len(alpha[i]) > 0:
                    it = bisect.bisect_left(alpha[i], int(b)-1)
                    if it < len(alpha[i]) and alpha[i][it] < int(c):
                        ans += 1
            print(ans)


main()
