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 bisect
import sys
input = lambda: sys.stdin.readline().rstrip()

n=int(input())
s= list(input())
q=[]
qq=int(input())
for i in range(qq):
    q.append(list(input().split()))

# アルファベットごとに出現位置を記録
x=[[] for i in range(26)]
for i,j in enumerate(s):
    x[ord(j)-97].append(i)

# 終点対策
for i in range(26):
    x[i].append(5*10**5)


for i,j,k in q:
    if int(i)==1:
        if s[int(j)-1]!=k:
            v=s[int(j)-1]
            s[int(j)-1]=k
            # 変更前の要素を削除
            index=bisect.bisect_right(x[ord(v)-97], int(j)-1) - 1
            x[ord(v)-97].pop(index)
            # 変更後の要素を加える
            bisect.insort_right(x[ord(k)-97],int(j)-1)
    else:
        cnt=0
        j=int(j)-1
        k=int(k)-1
        for l in range(26):
            index=bisect.bisect_left(x[l],j)
            if x[l][index]<=k:
                cnt+=1


        print(cnt)