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>
#define ll long long
using namespace std;
const int N=5e5+5;
char s[N],ss[5];
int f[N][26];
int n,q;
void update(int id,int pos,int val) {
	for(int i=pos;i<=n;i+=(i&-i)) {
		f[i][id]+=val;
	}
}
int query(int id,int pos) {
	int ans=0;
	for(int i=pos;i;i-=(i&-i)) {
		ans+=f[i][id];
	}
	return ans;
}
int main() {
	//freopen("in.txt","r",stdin);
	scanf("%d%s%d",&n,s+1,&q);
	for(int i=1;i<=n;i++) {
		int x=s[i]-'a';
		update(x,i,1);
	}
	for(int i=0,op,x,y;i<q;i++) {
		scanf("%d",&op);
		if(op==1) {
			scanf("%d%s",&x,ss);
			update(s[x]-'a',x,-1);
			update(ss[0]-'a',x,1);
			s[x]=ss[0];
		}
		else {
			scanf("%d%d",&x,&y);
			int ans=0;
			for(int j=0;j<26;j++) {
				if(query(j,y)-query(j,x-1)) ans++;
			}
			printf("%d\n",ans);
		}
	}
	return 0;
}