CF797B Odd sum

You are given sequence $ a_{1},a_{2},...,a_{n} $ of integer numbers of length $ n $ . Your task is to find such subsequence that its sum is odd and maximum among all such subsequences. It's guaranteed that given sequence contains subsequence with odd sum. Subsequence is a sequence that can be derived from another sequence by deleting some elements without changing the order of the remaining elements. You should write a program which finds sum of the best subsequence.

The first line contains integer number $ n $ ( $ 1

Print sum of resulting subseqeuence.

In the first example sum of the second and the fourth elements is $ 3 $ .