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())
s=[*input()]
q=int(input())
from collections import *
d=defaultdict(list)
for i,c in enumerate(s):
  d[c]+=[i]
from bisect import *
for _ in range(q):
  x,y,z=input().split()
  y=int(y)-1
  if x=='1':
    if s[y]==z: continue
    d[s[y]].pop(bisect(d[s[y]],y)-1)
    s[y]=z
    insort(d[z],y)
  else:
    print(sum(bisect(l,int(z)-1)-bisect_left(l,y)>0 for l in d.values()))