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())+1
w = input()
data=[0]*n*2
def update(i,x):
    i+=n
    data[i]=x
    i//=2
    while i:
      data[i]=data[i*2]|data[i*2+1]
      i//=2
def query(l,r):
    l+=n
    r+=n
    s=0
    while l<r:
      if l&1 == 1:
        s|=data[l]
        l+=1
      if r&1 == 1:
        r-=1
        s|=data[r]
      l//=2
      r//=2
    return bin(s).count('1')
def word_num(a):
    return 1<<(ord(a)-97)

for i in range(n-1):
    data[i+n] = word_num(w[i])    
for i in range(n-1,0,-1):
    data[i]=data[i*2]|data[i*2 + 1]

ans=[]
q=int(input())
for i in range(q):
    a,s,t=input().split()
    if a=='1':
        s=int(s)
        update(int(s)-1,word_num(t))
    if a=='2':
        s=int(s)
        t=int(t)
        ans.append(query(int(s)-1,int(t)))
for i in range(len(ans)):
    print(ans[i])