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 main(){
  int N;
  string S;
  int Q;
  cin >> N >> S >> Q;
  vector<set<int>> pos(26);
  for(int ii=0; ii<S.size(); ii++){
    pos[S[ii]-'a'].insert(ii);
  }
  for(int ii=0; ii<Q; ii++){
    int type;
    cin >> type;
    if(type==1){
      int a;
      char b;
      cin >> a >> b;
      a--;
      pos[S[a]-'a'].erase(a);
      pos[b-'a'].insert(a);
      S[a] = b;
    }else if(type==2){
      int a, b;
      cin >> a >> b;
      a--;
      b--;
      int ans=0;
      for(int jj=0; jj<26; jj++){
        auto it = pos[jj].lower_bound(a);
        if(it!=pos[jj].end()&&*it<=b) ans++;
      }
      cout << ans << endl;
    }
  }
  return 0;
}
