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,bisect_right,insort
N = int(input())
S = list(input())
Q = int(input())
D = dict()
D2 = dict()# to be removed
D3 = dict()# to be added

for i in range(97,97+26):
    D[chr(i)] = []
    D2[chr(i)] = []
    D3[chr(i)] = []
for i in range(N):
    D[S[i]].append(i+1)
for i in range(Q):
    t,l,r = input().split()
    if t == str(1):
        k = int(l)
        c = r
        if S[k-1] == c:
            continue
        if bisect_right(D[S[k-1]],k)-bisect_left(D[S[k-1]],k) == 1:
            del D[S[k-1]][bisect_left(D[S[k-1]],k)]
        insort(D[c],k)
        S[k-1] = c
        continue
    l = int(l)
    r = int(r)
    ans = 0
    for i in range(97,97+26):
        X = D[chr(i)]
        X2 = D2[chr(i)]
        X3 = D3[chr(i)]
        if bisect_right(X,r)-bisect_left(X,l) > 0:
            ans += 1
    print(ans)
