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
def main():
  import bisect
  
  n = int(input())
  s = list(input())
  q = int(input())
  
  d = {}
  for i in range(26):
    d[chr(ord('a')+i)] = []
  for i in range(n):
    d[s[i]].append(i)
  #print(d)
  
  for i in range(q):
    t,a,b = input().split()
    if t == '1':
      a = int(a)-1
      if s[a] == b:
        continue
      #idx = bisect.bisect_left(d[s[a]],a)
      #d[s[a]].pop(idx)
      d[s[a]].remove(a)
      bisect.insort_left(d[b],a)
      s[a] = b
    else:
      a = int(a)-1
      b = int(b)-1
      c = 0
      for i in range(26):
        idx = bisect.bisect_left(d[chr(ord('a')+i)],a)
        if idx < len(d[chr(ord('a')+i)]) and d[chr(ord('a')+i)][idx] <= b:
          c += 1
      print(c)
  
main()