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
#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main() {
	int N, Q;
	string S;
	cin >> N >> S >> Q;
	vector<set<int>> al(26);

	// 前処理
	for(int i=0;i<N;i++) {
		char c = S[i];
		al[c-'a'].insert(i);
	}

	for(int q=0;q<Q;q++) {
		int tmp;
		cin >> tmp;
		if(tmp == 1) {
			int i;
			char c;
			cin >> i >> c;
			i--;
			al[S[i]-'a'].erase(i);
			S[i] = c;
			al[c-'a'].insert(i);
		} else {
			int l, r;
			cin >> l >> r;
			l--, r--;
			int cnt = 0;
			for(int i=0;i<26;i++) {
				// l番目以上, r番目以下の数に'a'+iが存在するかどうか確かめる
				auto lb = al[i].lower_bound(l);
				auto ub = al[i].upper_bound(r);
				if(ub != lb) {
					cnt++;
				}
			}
			cout << cnt << endl;
		}
	}
}