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
from bisect import bisect_left,insort_left
n=int(input())
s=list(input())
lindex=[[] for _ in range(26)]
for i in range(n):
  lindex[ord(s[i])-97].append(i)
q=int(input())
for i in range(q):
  q1,q2,q3=input().split()
  if q1=='1':
    q2=int(q2)-1
    idx=bisect_left(lindex[ord(s[q2])-97],q2)
    if s[q2]!=q3:
      del lindex[ord(s[q2])-97][idx]
      insort_left(lindex[ord(q3)-97],q2)
      s[q2]=q3
  else:
    l=int(q2)-1
    r=int(q3)-1
    cnt=0
    for j in range(26):
      if len(lindex[j])==0:
        continue
      idx=bisect_left(lindex[j],l)
      if len(lindex[j])>idx and lindex[j][idx]<=r:
        cnt+=1
    print(cnt)