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 n,q;
string s;
int BIT[27][500001];

void update(int x,int y,int val)
{
	for(;x<=500000;x+=x&(-x))
		BIT[y][x] += val;
}

int query(int x,int y)
{
	int ans = 0;
	for(;x>0;x-=x&(-x))
		ans += BIT[y][x];
	return ans;
}

int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);

	cin >> n >> s >> q;
	s = '*' + s;
	for (int i=1;i<=n;i++)
		update(i,s[i] - 'a' + 1,1);
	while(q--)
	{
		int type;
		cin >> type;
		if (type == 1)
		{
			int pos; char c;
			cin >> pos >> c;
			update(pos,s[pos] - 'a' + 1,-1);
			update(pos,c - 'a' + 1,1);
			s[pos] = c;
		}
		else
		{
			int l,r;
			cin >> l >> r;
			int cnt = 0;
			for (int i=1;i<=26;i++)
				if (query(r,i) - query(l-1,i))
					cnt++;
			cout << cnt << '\n';						
		}
	}
}