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 a[500011][26];
int n;
int lowbit(int x){
	return x&-x;
}
int query(int x,int y){
	int res=0;
	for(int i=x;i;i-=lowbit(i)){
		res+=a[i][y];
	}
	return res;
}
void add(int x,int y,int v){
  for(int i=x;i<=n;i+=lowbit(i)){
	a[i][y]+=v;
}
}
int main(){
	int q;
	char s[500011];
	cin>>n;
	cin>>s+1>>q;
	for(int i=1;i<=n;i++){
		add(i,s[i]-'a',1);
	}
	while(q--){
		int op;
		cin>>op;
		if(op==1){
			char b;
			int c;
			cin>>c>>b;
			add(c,s[c]-'a',-1);
			s[c]=b;
			add(c,s[c]-'a',1);
		}
		else{
			int l,r;
			cin>>l>>r;
			int ans=0;
			for(int i=0;i<26;i++)
			if(query(r,i)-query(l-1,i)) ans++;
			cout<<ans<<'\n';
		}
	}
}