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.
-----Sample Input-----
7
abcdbbd
6
2 3 6
1 5 z
2 1 1
1 4 a
1 7 d
2 1 7
-----Sample Output-----
3
1
5
In the first query, cdbb contains three kinds of letters: b , c , and d, so we print 3.
In the second query, S is modified to abcdzbd.
In the third query, a contains one kind of letter: a, so we print 1.
In the fourth query, S is modified to abcazbd.
In the fifth query, S does not change and is still abcazbd.
In the sixth query, abcazbd contains five kinds of letters: a, b, c, d, and z, so we print 5.
n=int(input())+1
data=[0]*n*2
def update(i,x):
    i+=n
    data[i]=x
    i//=2
    while i:
        data[i]=data[i*2]|data[i*2+1]
        i//=2
def query(l,r):
    l+=n
    r+=n
    s=0
    while l<r:
        if l&1:
            s|=data[l]
            l+=1
        if r&1:
            r-=1
            s|=data[r]
        l//=2
        r//=2
    return sum(map(int,bin(s)[2:]))
s=input()
for i,c in enumerate(s,n):
    data[i]=1<<(ord(c)-97)
for i in range(n-1,0,-1):
    data[i]=data[2*i]|data[2*i+1]
for _ in range(int(input())):
    q,a,b=input().split()
    if q=="2":
        print(query(int(a)-1,int(b)))
    else:
        update(int(a)-1,1<<(ord(b)-97))
n=int(input())+1
data=[0]*n*2
def update(i,x):
    i+=n
    data[i]=x
    i//=2
    while i:
        data[i]=data[i*2]|data[i*2+1]
        i//=2
def query(l,r):
    l+=n
    r+=n
    s=0
    while l<r:
        if l&1:
            s|=data[l]
            l+=1
        if r&1:
            r-=1
            s|=data[r]
        l//=2
        r//=2
    return sum(map(int,bin(s)[2:]))
s=input()
for i,c in enumerate(s,n):
    data[i]=1<<(ord(c)-97)
for i in range(n-1,0,-1):
    data[i]=data[2*i]|data[2*i+1]
for _ in range(int(input())):
    q,a,b=input().split()
    if q=="2":
        print(query(int(a)-1,int(b)))
    else:
        update(int(a)-1,1<<(ord(b)-97))