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 as bl

n = int(input())
s = list(input())
q = int(input())
l = [[] for i in range(26)]
for i in range(n):
    l[ord(s[i])-ord("a")].append(i)
for i in range(q):
    x,y,z = input().split()
    if x == "1":
        y = int(y)-1
        if s[y] == z:
            continue
        b = ord(s[y])-ord("a")
        a = ord(z)-ord("a")
        l[b].pop(bl(l[b],y))
        l[a].insert(bl(l[a],y),y)
        s[y] = z
    if x == "2":
        count = 0
        for j in l:
            index = bl(j,int(y)-1)
            if index < len(j) and j[index] < int(z):
                count += 1
        print(count)