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 = input()
s = []
for i in range(n):
    s.append(S[i])
q = int(input())
BIT = []
for i in range(26):
    B = [0]*(n+1) #1-indexed
    BIT.append(B)

def sum_of_1_to_i(i, LIST):
    z = 0
    while i > 0:
        z += LIST[i]
        i -= i & (-i)
    return z

def update(i, j, LIST):
    while i <= n:
        LIST[i] += j
        i += i & (-i)

for i in range(n):
    k = ord(s[i])-97
    update(i+1, 1, BIT[k])

ans = []

for i in range(q):
    a,b,c = input().split()
    a = int(a)
    b = int(b)
    if a == 1:
        temp = s[b-1]
        if temp == c:
            None
        else:
            update(b, -1, BIT[ord(temp)-97])
            update(b, 1, BIT[ord(c)-97])
            s[b-1] = c
    else:
        c = int(c)
        cur = 0
        for j in range(26):
            if sum_of_1_to_i(c, BIT[j])-sum_of_1_to_i(b-1, BIT[j]) != 0:
                cur += 1
        ans.append(cur)
for i in range(len(ans)):
    print(ans[i])
