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 ctoi(c):
  return ord(c)-97

n=int(input())
s=list(input())

bits=[[0]*(n+1) for _ in range(26)]

def query(pos):
  ret=[0]*26
  for i in range(26):
    tmp=0
    p=pos
    while p>0:
      tmp+=bits[i][p]
      p-=p&(-p)
    ret[i]=tmp
  return ret

def update(pos,a,x):
  while pos<=n:
    bits[a][pos]+=x
    pos+=pos&(-pos)

for i in range(n):
  update(i+1,ctoi(s[i]),1)

q=int(input())
for _ in range(q):
  flag,a,b=map(str,input().split())
  flag=int(flag)
  a=int(a)
  if flag==1:
    if s[a-1]==b:
      continue
    else:
      update(a,ctoi(s[a-1]),-1)
      update(a,ctoi(b),1)
      s[a-1]=b
  elif flag==2:
    b=int(b)
    cnt1=query(b)
    cnt2=query(a-1)
    ans=0
    for i in range(26):
      if cnt1[i]-cnt2[i]>0:
        ans+=1
    print(ans)