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
# coding: utf-8
import sys
from bisect import bisect_left, bisect_right, insort_left
from collections import defaultdict

sr = lambda: sys.stdin.readline().rstrip()
ir = lambda: int(sr())
lr = lambda: list(map(int, sr().split()))

# 各アルファベットのindexのリストを作り,bisect_left()
N = ir()
S = list(sr())
dic = defaultdict(list)
for i, s in enumerate(S):
    dic[s].append(i)

Q = ir()
for _ in range(Q):
    a, b, c = sr().split()
    if a == '1':
        b = int(b) - 1
        if S[b] == c:
            continue
        dic[S[b]].remove(b)
        insort_left(dic[c], b)
        S[b] = c
    else:
        b = int(b) - 1; c = int(c) - 1
        kind = 0
        for x in range(26):
            word = chr(ord('a')+x)
            if len(dic[word]) == 0:
                continue
            i = bisect_left(dic[word], b)
            j = bisect_right(dic[word], c)
            if i != j:
                kind += 1
        print(kind)

# 07