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>

#include <iostream>


#define MOD 1000000007

typedef unsigned long long ull;
typedef long long ll;

using namespace std;
auto f=[]()
{
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr);
};


int main()
{
	f();
	vector<set<int>> v(26);
	int n;cin>>n;
	for(auto i=1;i<=n;++i)
	{
		char c;cin>>c;
		v[c-'a'].insert(i);
	}
	
	int q;cin>>q;
	while(q--)
	{
		int t;cin>>t;
		if(t==1)
		{
			size_t id;
			char c;
			cin>>id>>c;
			
			for(auto j=0;j<26;++j)
				v[j].erase(id);
			
			v[c-'a'].insert(id);
		}
		else
		{
			size_t l,r;cin>>l>>r;
			size_t ans=0;
			for(auto i=0;i<26;++i)
			{
				auto it=v[i].lower_bound(l);
				if(it!=v[i].end() && *it<=r)
					ans++;
			}
			cout<<ans<<"\n";
		}
	}
	return 0;
}
