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,bisect_right,insort

n = int(input())
s = list("-" + str(input()))
lis = [[] for i in range(26)]
for i in range(1,n+1):
    num = ord(s[i])-ord("a")
    lis[num].append(i)

q = int(input())
for turn in range(q):
    query = list(map(str,input().split()))
    if query[0] == "1":
        a = int(query[1])
        if s[a] == query[2]:
            continue
        num = ord(s[a])-ord("a")
        lis[num].pop(bisect_left(lis[num],a))
        next = ord(query[2])-ord("a")
        insort(lis[next],a)
        s[a] = query[2]
    else:
        a,b = int(query[1]),int(query[2])
        ans = 0
        for alphabet in range(26):
            if bisect_right(lis[alphabet],b)-bisect_left(lis[alphabet],a) >= 1:
                ans += 1
        print(ans)