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
import sys
input = sys.stdin.readline
N = int(input())
S = input().rstrip()
Q = int(input())
qs = [input().split() for i in range(Q)]

def ctoi(c):
    return ord(c) - ord('a')

bit = [[0]*(N+2) for _ in range(26)]
def bit_add(x,w,ci):
    while x <= N+1:
        bit[ci][x] += w
        x += (x & -x)
def bit_sum(x,ci):
    ret = 0
    while x > 0:
        ret += bit[ci][x]
        x -= (x & -x)
    return ret

for i,c in enumerate(S):
    bit_add(i+1,1,ctoi(c))

s = list(S)
ans = []
for a,b,c in qs:
    if a=='1':
        x = int(b)
        bit_add(x,1,ctoi(c))
        bit_add(x,-1, ctoi(s[x-1]))
        s[x-1] = c
    else:
        tmp = 0
        for i in range(26):
            if bit_sum(int(c),i) - bit_sum(int(b)-1,i) > 0:
                tmp += 1
        ans.append(tmp)
print(*ans, sep='\n')