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
#####segfunc######
def segfunc(x,y):
  return x|y 

def init(init_val):
  #set_val
  for i in range(n):
    seg[i+num-1]=init_val[i]  
  #built
  for i in range(num-2,-1,-1) :
    seg[i]=segfunc(seg[2*i+1],seg[2*i+2]) 
  
def update(k,x):
  k += num-1
  seg[k] = x
  while k:
    k = (k-1)//2
    seg[k] = segfunc(seg[k*2+1],seg[k*2+2])
  
def query(p,q):
  if q<=p:
    return ide_ele
  p += num-1
  q += num-2
  res=ide_ele
  while q-p>1:
    if p&1 == 0:
      res = segfunc(res,seg[p])
    if q&1 == 1:
      res = segfunc(res,seg[q])
      q -= 1
    p = p//2
    q = (q-1)//2
  if p == q:
    res = segfunc(res,seg[p])
  else:
    res = segfunc(segfunc(res,seg[p]),seg[q])
  return res

#####単位元######
ide_ele = set([])

#num:n以上の最小の2のべき乗
n = int(input())
S = [set([s]) for s in input()]
num =2**(n-1).bit_length()
seg=[ide_ele]*2*num

init(S)
q = int(input())
for _ in range(q):
  a,b,c = input().split()
  if a == '1':
    b = int(b)-1
    update(b, set([c]))
  elif a == '2':
    b = int(b)-1
    c = int(c)
    print(len(query(b,c)))