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;
int main(){
	int N, Q; string S; 
	cin >> N >> S >> Q;
	set<int> T[26]; 
	for(int i = 0; i < 26; i++){
		T[i].insert(-1145141919); 
		T[i].insert(1145141919); 
	}
	for(int i = 1; i <= N; i++){
		int a = S.at(i-1) - 'a';  
		T[a].insert(i); 
	}
	while(Q--){
		int a; cin >> a; 
		if(a == 1){
			int x; char c; cin >> x >> c; 
			T[S.at(x-1) - 'a'].erase(x);  
			T[c - 'a'].insert(x); 
			S.at(x-1) = c; 
		}
		if(a == 2){
			int x, y; cin >> x >> y; 
			int cnt = 0; 
			for(int i = 0; i < 26; i++){
				if(*T[i].lower_bound(x) <= y) cnt ++; 
			}
			cout << cnt << endl; 
		}
	} 
}