Wet Shark and Odd and Even

输入N个正整数选择其中的几个，组成最大的偶数（如果不选输出0）

Today, Wet Shark is given $ n $ integers. Using any of these integers no more than once, Wet Shark wants to get maximum possible even (divisible by $ 2 $ ) sum. Please, calculate this value for Wet Shark. Note, that if Wet Shark uses no integers from the $ n $ integers, the sum is an even integer $ 0 $ .

The first line of the input contains one integer, $ n $ ( $ 1<=n<=100000 $ ). The next line contains $ n $ space separated integers given to Wet Shark. Each of these integers is in range from $ 1 $ to $ 10^{9} $ , inclusive.

Print the maximum possible even sum that can be obtained if we use some of the given integers.

3
1 2 3

6

5
999999999 999999999 999999999 999999999 999999999

3999999996

In the first sample, we can simply take all three integers for a total sum of $ 6 $ . In the second sample Wet Shark should take any four out of five integers $ 999999999 $ .