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;
set <int> q[26];
int n,op,x,l,r,t,len,cnt;
char s[500001]; 
char c;
 
 
int main(){
	int n;
	cin >> n;
	cin>>s;
	len=strlen(s);
	for (int i=0;i<len;i++) q[s[i]-97].insert(i);
	cin>>n;
	for (int i=1;i<=n;i++){
		cin>>op;
		if (op==1){
			cin>>x>>c;
			x--;
			q[s[x]-97].erase(x);
			s[x]=c;
			q[c-97].insert(x);
		}
		if (op==2){
			cin>>l>>r;
			l--;r--;
			cnt=0;
			for (int j=0;j<=25;j++) if (*q[j].lower_bound(l)<=r&&q[j].lower_bound(l)!=q[j].end()) cnt++;
			cout<<cnt<<endl;
		}
	}
}