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
f=input
n,l,q=int(f()),list(f()),int(f())
B=[[0]*-~n for i in range(26)]
def S(o,i):
  s=0
  while i: s+=B[o][i]; i-=i&-i
  return s
def A(o,i,x):
  while i<=n: B[o][i]+=x; i+=i&-i
for i in range(n): A(ord(l[i])-97,i+1,1)
for i in range(q):
  a,b,c=f().split(); b=int(b)
  if a>'1': print(sum(1 for o in range(26) if S(o,int(c))-S(o,b-1)))
  else: A(ord(l[b-1])-97,b,-1); l[b-1]=c; A(ord(c)-97,b,1)