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
range = xrange
input = raw_input

class segtree:
    def __init__(self, n):
        m = 1
        while m < n:
            m *= 2
        self.m = m
        self.data = [0]*(m + m)
    def add(self, i, x):
        i += self.m
        while i:
            self.data[i] += x
            i >>= 1

    def summer(self, l ,r):
        l += self.m
        r += self.m
        while l < r:
            if l & 1:
                if self.data[l]:
                    return True
                l += 1
            if r & 1:
                r -= 1
                if self.data[r]:
                    return True
            l >>= 1
            r >>= 1
        return False

orda = ord('a')

inp = sys.stdin.read().split(); ii = 0

n = int(inp[ii]); ii += 1
S = [ord(c) - orda for c in inp[ii]]; ii += 1

segs = [segtree(n) for _ in range(26)]
for i in range(n):
    segs[S[i]].add(i, 1)

q = int(inp[ii]); ii += 1
out = []
for _ in range(q):
    case = int(inp[ii]); ii += 1

    if case == 1:
        i = int(inp[ii]) - 1; ii += 1
        c = ord(inp[ii]) - orda; ii += 1

        segs[S[i]].add(i, -1)
        S[i] = c
        segs[S[i]].add(i, 1)
    else:
        l = int(inp[ii]) - 1; ii += 1
        r = int(inp[ii]); ii += 1
        out.append(sum(seg.summer(l,r) for seg in segs))
print '\n'.join(str(x) for x in out)
