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_right
from bisect import bisect_left

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

ind_list = [[] for _ in range(26)]

for i, x in enumerate(s):
    ind_list[ord(x)-97].append(i)

for _ in range(q):
    _type, val1, val2 = input().split()
    if _type == '1':
        i = int(val1)-1
        c = val2
        if s[i] == c:
            continue
        ind_list[ord(s[i])-97].remove(i)
        p = bisect_right(ind_list[ord(c)-97], i)
        ind_list[ord(c)-97].insert(p, i)
        s[i] = c
    elif _type == '2':
        l = int(val1)-1
        r = int(val2)-1
        ans = 0
        for i in range(26):
            if bisect_right(ind_list[i], r) - bisect_left(ind_list[i], l) > 0:
                ans += 1
        print(ans)
    else:
        print('Exception caught!')
        exit()
