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
// ABC157E - Simple String Queries

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

int main() {
	int N;
	cin >> N;

	vector< set<int> > alpha(26);

	for (int i = 0; i < N; i++) {
		char c;
		cin >> c;
		alpha[c - 'a'].insert(i + 1);
	}

	int Q;
	cin >> Q;
	for (int i = 0; i < Q; i++) {
		int op;
		cin >> op;
		if (op == 1) {
			int iq;
			char cq;
			cin >> iq >> cq;

			for (int j = 0; j < 26; j++) {
				alpha[j].erase(iq);
			}
			alpha[cq - 'a'].insert(iq);
		} else if (op == 2) {
			int l, r;
			cin >> l >> r;

			int answer = 0;
			for (int j = 0; j < 26; j++) {
				set<int>::iterator it;
				it = alpha[j].lower_bound(l);
				if ((it != alpha[j].end())&&(*it <= r)) {
					answer++;
				};
			}
			cout << answer << endl;
		}
	}
}
