PivotOJ

Moon and Sun

시간 제한: 1000ms메모리 제한: 512MB출처: ICPC Asia Jakarta Regional 2020BOJ 20687

문제

Let SS be a non-empty sequence of integers and KK be a positive integer. The functions moon()moon() and sun()sun() are defined as follows.

moon\left(S_{1\dots|S|}\right) = \begin{cases} S & \text{if } |S| = 1 \\ \left[ S_2 − S_1, S_3 − S_2, \dots , S_{|S|} − S_{|S|−1} \right] & \text{if }|S| > 1 \end{cases}

sun\left(S_{1\dots|S|}, K\right) = \begin{cases} S & \text{if } K = 1 \\ sun\left(moon\left(S_1\dots|S|\right), K − 1\right) & \text{if }K > 1 \end{cases}

For example,

  • moon([2,7])=[5]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(S1S,S)sun\left(S_{1\dots |S|}, |S|\right) is always a sequence with exactly one element.

You are given a sequence of NN integers A1NA_{1\dots N}. An index i=[1N]i = [1\dots N] is hot if and only if there exists a sequence A1NA'_{1\dots N} satisfying the following conditions.

  • AiAiA'_i \ne A_i and AiA_i' is an integer between 100000-100 000 and 100000100 000, inclusive;
  • Aj=AjA'_j = A_j for all jij \ne i;
  • The only element in sun(A1N,N)sun\left(A'_{1\dots N}, N\right) is a multiple of 235813235 813.

Your task in this problem is to count the number of hot indices in a given A1NA_{1\dots N}.

For example, there are 33 hot indices in A15=[4,1,0,7,2]A_{1\dots 5} = [4, 1, 0, 7, 2], which are {1,3,5}\{1, 3, 5\}.

  • i=1  A1=30A15=[30,1,0,7,2]sun([30,1,0,7,2],5)=[0]i = 1 ~~ A'_1 = 30 \rightarrow A'_{1\dots5} = [30, 1, 0, 7, 2] \rightarrow sun([30, 1, 0, 7, 2], 5) = [0]
  • i = 3 ~~ A'_1 = −78 600 \rightarrow A'_{1\dots5} = [4, 1, −78 600, 7, 2] \rightarrow sun([4, 1, −78 600, 7, 2], 5) = [−471 626]
  • i=5  A1=28A15=[4,1,0,7,28]sun([4,1,0,7,28],5)=[0]i = 5 ~~ A'_1 = 28 \rightarrow A'_{1\dots5} = [4, 1, 0, 7, 28] \rightarrow sun([4, 1, 0, 7, 28], 5) = [0]

Note that both 00 and 471626-471 626 are multiples of 235813235 813. On the other hand, the index i=2i = 2 is not hot as there does not exist an integer A2A2A'_2 \ne A_2 between 100000-100 000 and 100000100 000, inclusive, such that the only element in sun(A15,5)sun(A'_{1\dots 5} , 5) is a multiple of 235813235 813. The index i=4i = 4 is also not hot for a similar reason.

입력

Input begins with a line containing an integer: NN (1N1000001 \le N \le 100 000) representing the number of integers in AA. The next line contains NN integers: AiA_i (100000Ai100000-100 000 \le A_i \le 100 000) representing the sequence of integers.

출력

Output in a line an integer representing the number of hot indices in the given A1NA_{1\dots N} .

예제

예제 1

입력
5
4 1 0 7 2
출력
3

예제 2

입력
4
10 20 30 -40
출력
4

예제 3

입력
2
100 100
출력
0
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