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
#  --*-coding:utf-8-*--

import bisect

N = int(input())
indexess = [[] for _ in range(26)]

S = list(input())
for i, s in enumerate(S):
    indexess[ord(s) - 97].append(i)


Q = int(input())
for _ in range(Q):
    q1,q2, q3 = input().split()
    q2 = int(q2)

    if q1 == '1':
        s0 = S[q2-1]
        if s0 != q3:
            S[q2-1] = q3
            
            indexes = indexess[ord(s0) - 97]
            del indexes[bisect.bisect_left(indexes, q2-1)]
            bisect.insort(indexess[ord(q3) - 97], q2-1)

    else:
        cnt = 0
        q3 = int(q3)
        for indexes in indexess:
            
            if bisect.bisect_left(indexes, q2-1) < bisect.bisect_right(indexes, q3-1):
                cnt += 1

        print(cnt)
