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
n = int(input())
S = list(input())
q = int(input())

import sys
input = sys.stdin.readline

alp = "abcdefghijklmnopqrstuvwxyz"
appr = {a:[] for a in alp}

import bisect

for i, a in enumerate(S):
  appr[a].append(i+1)
#print(appr)
for i in range(q):
  inputs = input().split()
  if inputs[0] == '1':
    c = int(inputs[1])
    a = inputs[2]
    if S[c-1]==a:
      continue
    else:
      old = S[c-1]
      S[c-1] = a
      del_idx = bisect.bisect_left(appr[old], c)
      del appr[old][del_idx]
      in_idx = bisect.bisect_left(appr[a], c)
      appr[a].insert(in_idx, c)
  else:
    l, r = map(int, inputs[1:])
    res = 0
    for a in appr:
      l_idx = bisect.bisect_left(appr[a], l)
      if l_idx<len(appr[a]):
        if appr[a][l_idx]<=r:
          res += 1
    print(res)
    
#print(appr)