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
n = int(input())
s = list(input())
BITs = [[0]*(n+1) for _ in range(26)]

def c_idx(c):
    return ord(c) - 97

def query(pos):
    ret = [0]*26
    for i in range(26):
        tmp = 0
        p = pos
        while p > 0:
            tmp += BITs[i][p]
            p -= p & (-p)
        ret[i] = tmp
    return ret

def update(pos, a, x):
    while pos <= n:
        BITs[a][pos] += x
        pos += pos & (-pos)

for i in range(n):
    update(i+1, c_idx(s[i]), 1)
#print(BITs)

q = int(input())
for _ in range(q):
    a, b, c = input().split()
    b = int(b)
    if a == "1":
        if s[b-1] == c:
            continue
        update(b, c_idx(s[b-1]), -1)
        update(b, c_idx(c), 1)
        s[b-1] = c
    else:
        c = int(c)
        count1 = query(c)
        count2 = query(b-1)
        ans = 0
        for i in range(26):
            if count1[i] - count2[i] > 0:
                ans += 1
        print(ans)