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
# -*- coding: utf-8 -*-
"""
Created on Sat Jun 15 22:01:38 2019

@author: aozora
"""
class BIT:
  def __init__(self,n):
    self.N = n
    self.data = [0]*(N+1)
  def bit_add(self,i,a):
    j = i+1
    while j<=N:
      self.data[j] += a
      j += j&-j
  def bit_sum(self,i):
    m = 0
    j = i+1
    while j>0:
      m += self.data[j]
      j -= j&-j
    return m
N = int(input())
S = list(input())
Q = int(input())
dic = [0]*26
s = ord('a')
for i in range(26):
  dic[i] = BIT(N)
for i, c in enumerate(S):
  c = ord(c)-s
  dic[c].bit_add(i,1)
for i in range(Q):
  t, a, b = input().split()
  t = int(t)
  if t==1:
    a = int(a)-1
    c = S[a]
    S[a] = b
    b = ord(b)-s
    c = ord(c)-s
    dic[b].bit_add(a,1)
    dic[c].bit_add(a,-1)
  else:
    a = int(a)
    b = int(b)
    ans = 0
    a -= 1
    b -= 1
    for i in range(26):
      if a>0:
        z = dic[i].bit_sum(b)-dic[i].bit_sum(a-1)
      else:
        z = dic[i].bit_sum(b)
      if z>0:
        ans += 1
    print(ans)