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())
s=input()
q=int(input())
dic=dict()
for i,j in enumerate("qwertyuioplkjhgfdsazxcvbnm"):
    dic[j]=i
No=2
while n>No:
    No*=2
tree=[set()]*(2*No)
def add(k,x):
    k+=No-1
    tree[k]=set([dic[x]])
    while k>0:
        k=(k-1)//2
        tree[k]=tree[2*k+1]|tree[2*k+2]
def query(l,r):
    L=l+No-1
    R=r+No-1
    s=set()
    while L<=R:
        if R&1:
            s|=tree[R]
            R-=2
        else:
            R-=1
        if L&1:
            L-=1
        else:
            s|=tree[L]
        L>>=1;R>>=1
    return len(s)
for i,j in enumerate(s):
    tree[i+No-1]=set([dic[j]])
for i in range(No-2,-1,-1):
    tree[i]=tree[2*i+1]|tree[2*i+2]
for i in range(q):
    a,b,c=input().split()
    a,b=int(a),int(b)
    if a==1:
        add(b-1,c)
    if a==2:
        c=int(c)
        print(query(b-1,c-1))