题目描述
Let S be a non-empty sequence of integers and K be a positive integer. The functions moon() and sun() are defined as follows.
$$moon(S_{1..|S|}) =
\begin{cases}
S & \text{if } |S| = 1 \\
[S_2 - S_1, S_3 - S_2, \dots, S_{|S|} - S_{|S|-1}] & \text{if } |S| > 1
\end{cases}
$$$$sun(S_{1..|S|}, K) =
\begin{cases}
S & \text{if } K = 1 \\
sun(moon(S_{1..|S|}), K - 1) & \text{if } K > 1
\end{cases}
$$
For example,
- moon([2,7])=[5].
- moon([4,1,0,7,2])=[−3,−1,7,−5].
- $sun([4, 1, 0, 7, 2], 5) = sun([-3, -1, 7, -5], 4) = sun([2, 8, -12], 3) = sun([6, -20], 2) = sun([-26], 1) = [-26]$.
Observe that sun(S1..∣S∣,∣S∣) is always a sequence with exactly one element.
You are given a sequence of N integers A1..N. An index i=[1..N] is hot if and only if there exists a sequence A1..N′ satisfying the following conditions:
- Ai′=Ai and Ai′ is an integer between −100000 and 100000, inclusive;
- Aj′=Aj for all j=i;
- The only element in sun(A1..N′,N) is a multiple of 235813.
Your task in this problem is to count the number of hot indices in a given A1..N.
For example, there are 3 hot indices in A1..5=[4,1,0,7,2], which are {1,3,5}.
- i=1, A1′=30 → A1..5′=[30,1,0,7,2] → sun([30,1,0,7,2],5)=[0]
- i=3, A1′=−78600 → A1..5′=[4,1,−78600,7,2] → sun([4,1,−78600,7,2],5)=[−471626]
- i=5, A1′=28 → A1..5′=[4,1,0,7,28] → sun([4,1,0,7,28],5)=[0]
Note that both 0 and −471626 are multiples of 235813. On the other hand, the index i=2 is not hot as there does not exist an integer A2′=A2 between −100000 and 100000, inclusive, such that the only element in sun(A1..5′,5) is a multiple of 235813. The index i=4 is also not hot for a similar reason.
输入格式
Input begins with a line containing an integer: N (1≤N≤100000) representing the number of integers in A. The next line contains N integers: Ai (−100000≤Ai≤100000) representing the sequence of integers.
输出格式
Output in a line an integer representing the number of hot indices in the given A1..N.
5
4 1 0 7 2
3
4
10 20 30 -40
4
2
100 100
0
提示
This is the example from the problem description.
- i=1, A1′=−70 → A1..4′=[−70,20,30,−40] → sun([−70,20,30,−40],4)=[0]
- i=2, A2′=78651 → A1..4′=[10,78651,30,−40] → sun([10,78651,30,−40],4)=[235813]
- i=3, A3′=−78601 → A1..4′=[10,20,−78601,−40] → sun([10,20,−78601,−40],4)=[235813]
- i=4, A4′=40 → A1..4′=[10,20,30,40] → sun([10,20,30,40],4)=[0]