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 math

n = int(input())
s = input()
S = [ord(i) - 97 for i in s]
q = int(input())
HEIGHT = math.ceil(math.log(n) / math.log(2))
SIZE = 1 << HEIGHT

def build_tree():
    tree = [0 for _ in range(SIZE<<1)]

    for i, letter in enumerate(s):
        tree[i+SIZE] = 1<<(ord(letter)-97)

    for i in range(HEIGHT - 1, -1, -1):
        for x in range(1<<i, 2<<i):
            tree[x] = tree[x<<1] | tree[(x<<1)+1]

    return tree




def update(x, number):
    tree[x] = number
    while x > 1:
        x >>= 1
        tree[x] = tree[x << 1] | tree[(x << 1) + 1]


def query(l, r):
    total = 0
    while l < r:
        if l&1:
            total |= tree[l]
            l += 1
        l >>= 1
        if r&1:
            r -= 1
            total |= tree[r]
        r >>= 1
    return bin(total).count('1')



tree = build_tree()

for i in range(q):
    a, b, c = input().split()
    b = int(b) - 1
    if int(a) == 1:
        update(b + SIZE, S[b])
        c = 1 << (ord(c) - 97)
        S[b] = c
        update(b + SIZE, c)
    else:
        print(query(b + SIZE, int(c)+SIZE))






