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;
const int INF = 1e9;

signed main(){
	int n; cin >> n;
	string s; cin >> s;
	int q; cin >> q;
	vector<set<int> > SET(26, set<int> {INF});
	for(int i = 0; i < n; i++) SET[s[i] - 'a'].insert(i);
	for(int i = 0; i < q; i++){
		int type; cin >> type;
		if(type == 1){
			int l; cin >> l; char c; cin >> c; --l;
			if(s[l] != c){
			  SET[s[l] - 'a'].erase(l);
			  SET[c - 'a'].insert(l);
			  s[l] = c;
			}
		}
		if(type == 2){
			int l, r; cin >> l >> r; --l;
			int c = 0;
			for(int j = 0; j < 26; j++){
				if(SET[j].empty()) continue;
				if(*SET[j].lower_bound(l) < *SET[j].lower_bound(r)) c++;
			}
			cout << c << endl;
		}
	}
}
