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
#!/usr/bin python3
# -*- coding: utf-8 -*-

from bisect import bisect_left, bisect_right


n = int(input())
s = list(input())
q = int(input())

al = 'abcdefghijklmnopqrstuvwxyz'
dicq = {i:[] for i in al}
for i, si in enumerate(s):
    dicq[si].append(i)

def q1(iq, cq):
    #print(iq,cq,s[iq],dicq[s[iq]],bisect_left(dicq[s[iq]], iq))
    dicq[s[iq]].pop(bisect_left(dicq[s[iq]], iq))   #更新前から削除
    s[iq] = cq
    dicq[cq].insert(bisect_left(dicq[cq], iq), iq)   #更新後に追加

def q2(l, r):
    ret = 0
    for ai in al:
        if len(dicq[ai])==0: continue
        li = bisect_left(dicq[ai], l)
        ri = bisect_right(dicq[ai], r)
        if li != ri:
            ret += 1
        elif li == len(dicq[ai]): continue
        elif dicq[ai][li] == l:
            ret += 1
    #    print(l,r,ai,dicq[ai],li,ri,ret)
    print(ret)

for i in range(q):
    fg, x, y = input().split()
    if fg == '1':
        q1(int(x)-1, y)
    else:
        q2(int(x)-1, int(y)-1)
