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"atcoder/all"
#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
using namespace std;
//using namespace atcoder;
typedef long long ll;
int main(){
  cin.tie(nullptr);ios::sync_with_stdio(false);
  int N,Q,i,j,cnt;string s;cin >> N >> s >> Q;
  set<int> al[26];
  for(i=0;i<26;i++) al[i].insert(N);
  for(i=0;i<N;i++) al[s[i]-'a'].insert(i);
  int q,k,l,r;char c;
  for(i=0;i<Q;i++){
    cin >> q;
    if(q == 1){
      cin >> k >> c;k--;
      al[s[k]-'a'].erase(k);
      al[c-'a'].insert(k);
      s[k] = c;
    }
    else{
      cin >> l >> r;l--;r--;
      cnt = 0;
      for(j=0;j<26;j++) cnt += *al[j].lower_bound(l) <= r;
      cout << cnt << "\n"; 
    }
  }
}