A10914. 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 $n$ ( $1<=n<=10^{5}$ ).

The second line contains $n$ integer numbers $a_{1},a_{2},...,a_{n}$ ( $-10^{4}<=a_{i}<=10^{4}$ ). The sequence contains at least one subsequence with odd sum.

Print sum of resulting subseqeuence.

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