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
readline = sys.stdin.readline

from bisect import bisect_left, insort_left

def main():
    n = int(readline())
    s = list(readline().rstrip())
    q = int(readline())
    
    chk_abc = [[] for i in range(26)]
    for i, si in enumerate(s):
        ci = ord(si) - 97
        chk_abc[ci].append(i)
        
    ans = []
    for _ in range(q):
        cmd, i, j = readline().rstrip().split()
        i = int(i) - 1
        
        if cmd == "1":
            if s[i] == j:
                continue
            c1 = ord(s[i]) - 97
            prev = chk_abc[c1]
            c2 = ord(j) - 97
            prev.pop(bisect_left(prev, i))
            s[i] = j
            insort_left(chk_abc[c2], i)
            
        else:
            j = int(j) - 1
            num = 0
            for chk in chk_abc:
                le = len(chk)
                k = bisect_left(chk, i, 0, le)
                if k == le:
                    continue
                if i <= chk[k] <= j:
                    num += 1
            ans.append(num)

    print(*ans, sep="\n")

if __name__ == "__main__":
    main()