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
n=int(input())
from bisect import bisect_left,bisect_right
s=list(input())
q=int(input())
D={chr(ord("a")+i):[] for i in range(26)}
for i ,j in enumerate(s):
    D[j].append(i)
ans=0
for i in range(q):
    x=list(input().split())
    if x[0]=="1":
        l=int(x[1])
        l-=1
        r=x[-1]
        if r==s[l]:
            continue
        rr=bisect_left(D[r],l)
        D[s[l]].remove(l)
        D[r].insert(rr,l)
        s[l]=r
    else:
        l=int(x[1])
        r=int(x[2])
        l-=1
        r-=1
        ans=0
        for i in range(26):
            W=chr(ord("a")+i)
            ll=bisect_left(D[W],l)
            rr=bisect_right(D[W],r)
            if rr-ll>0:
                ans+=1
        print(ans)

