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()

seg = [0]*(2*N-1)

def update(k, x):
    k += N-1
    seg[k] = 2**x
    while k:
        k = (k-1)//2
        seg[k] = seg[2*k+1] | seg[2*k+2]
        
def query(p, q):
    p += N-1
    q += N-2
    res = 0
    while q-p > 1:
        if p&1 == 0:
            res = res | seg[p]
        if q&1 == 1:
            res = res | seg[q]
            q -= 1
        p //= 2
        q = (q-1)//2
    if p == q:
        res |= seg[q]
    else:
        res |= seg[p] | seg[q]
    return bin(res).count("1")

def f(s):
    return ord(s) - ord("a") + 1

for i in range(N):
    update(i, f(S[i]))
    
Q = int(input())
for _ in range(Q):
    a,b,c = map(str, input().split())
    if a == "1":
        update(int(b)-1, f(c))
    else:
        print(query(int(b)-1, int(c)))