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;
 
#define ll long long
#define pb push_back
#define mp make_pair
#define mo 1000000007
#define MAX_N 500004
#define INF 2000000000
 
#define fast_io ios::sync_with_stdio(false)


set<int> st[26];

int main()
{
	int n, q, ty, l, r;
	char c;
	string s;
	cin >> n >> s >> q;
	for(int i = 0; i < n; ++i)
		st[s[i] - 'a'].insert(i);
	for(int i = 1; i <= q; ++i)
	{
		cin >> ty;
		if(ty == 1)
		{
			cin >> l >> c;
			l--;
			st[s[l] - 'a'].erase(l);
			st[c - 'a'].insert(l);
			s[l] = c;
		}  
		else
		{
			cin >> l >> r;
			l--;
			r--;
			int ans = 0;
			for(int i = 0; i < 26; ++i)
				if(st[i].lower_bound(l) != st[i].end() && *st[i].lower_bound(l) <= r)
					ans++;
			cout << ans << endl;
		}

	}



}   