1741: A Series

An arithmetic series consists of a sequence of terms such that each term minus its immediate predecessor gives the same result. For example, the sequence 3,7,11,15 is the terms of the arithmetic series 3+7+11+15; each term minus its predecessor equals 4. (Of course there is no requirement on the first term since it has no predecessor.) Given a collection of integers, we want to find the longest arithmetic series that can be formed by choosing a sub-collection (possibly the entire collection). Create a class ASeries that contains a method longest that is given a int[] values and returns the length of the longest arithmetic series that can be formed from values.

Line 1:the number of int[] values, between 2 and 50 . Line 2:Each element of values will be between -1,000,000 and 1,000,000 inclusive.There is a space between each two elements.

There will be only one line showing the biggest length of the arithmetic series.

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3 8 4 5 6 2 2

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