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,Q,a,b,e,ans;
  string S;
  char c,d;
  cin>>N>>S>>Q;
  unordered_map<char,set<int>> mp;
  for(int i=0;i<N;i++){
    mp[S.at(i)].insert(i);
  }
  for(int i=0;i<Q;i++){
    cin>>a;//1か2か
    if(a==1){
      cin>>b>>c;
      d=S.at(b-1);
      S.at(b-1)=c;
      mp[d].erase(b-1);
      mp[c].insert(b-1);
    }
    else{
      cin>>b>>e;
      ans=0;
      for(char j='a';j<='z';j++){
        if(mp[j].size()==0){continue;}
        auto it=mp[j].rbegin();
        if(*it<b-1){continue;}
        auto itr=mp[j].lower_bound(b-1);
        if(*itr<=e-1){ans++;}
      }
      cout<<ans<<endl;
    }
  }
}