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
import bisect

N = int(input())
S = input()
Q = int(input())
alphabet_dic = {}
alphabet_array = []
for i,s in enumerate(S):
    alphabet_array.append(s)
    if s in alphabet_dic:
        alphabet_dic[s].append(i)
    else:
        alphabet_dic[s] = [i]
# print(alphabet_dic)

for _ in range(Q):
    a, b, c = map(str,input().split())
    if int(a) == 1:
        b = int(b)
        now_str = alphabet_array[b-1]
        if now_str != c:
            alphabet_array[b-1] = c
            alphabet_dic[now_str].remove(b-1)
            if c in alphabet_dic:
                bisect.insort_left(alphabet_dic[c],b-1)
            else:
                alphabet_dic[c] = [b-1]
    else:
        ans = 0
        b = int(b)
        c = int(c)
        for index_array in alphabet_dic.values():
            if not len(index_array) or index_array[-1] < b-1:
                continue
            i = bisect.bisect_left(index_array,b-1)
            if index_array[i] <= c-1:
                ans += 1
        print(ans)
