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;
  string s;
  cin >> n >> s >> q;
  vector<set<int>> pos(26);
  for (int i = 0; i < n; i++) {
    int idx = s[i] - 'a';
    pos[idx].insert(i);
  }
  while (q--) {
    int type;
    cin >> type;
    if (type == 1) {
      int t;
      char c;
      cin >> t >> c;
      t--;
      int idx = c - 'a';
      int pre = s[t] - 'a';
      s[t] = c;
      pos[pre].erase(t);
      pos[idx].insert(t);
      continue;
    }
    int l, r;
    cin >> l >> r;
    l--;
    r--;
    int ret = 0;
    for (int i = 0; i < 26; i++) {
      auto itr = pos[i].lower_bound(l);
      if (itr == pos[i].end()) continue;
      if (*itr <= r) ret++;
    }
    cout << ret << endl;
  }
}