You are given sequence *a*<sub class="lower-index">1</sub>, *a*<sub class="lower-index">2</sub>, ..., *a*<sub class="lower-index">*n*</sub> 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<sup class="upper-index">5</sup>).

The second line contains *n* integer numbers *a*<sub class="lower-index">1</sub>, *a*<sub class="lower-index">2</sub>, ..., *a*<sub class="lower-index">*n*</sub> ( - 10<sup class="upper-index">4</sup> ≤ *a*<sub class="lower-index">*i*</sub> ≤ 10<sup class="upper-index">4</sup>). The sequence contains at least one subsequence with odd sum.
In the first example sum of the second and the fourth elements is 3.
4
-2 2 -3 1
3
3
2 -5 -3
-1
1
1
1
1
-1
-1
15
-6004 4882 9052 413 6056 4306 9946 -4616 -6135 906 -1718 5252 -2866 9061 4046
53507
2
-5439 -6705
-5439
2
2850 6843
9693
2
144 9001
9145
10
7535 -819 2389 4933 5495 4887 -5181 -9355 7955 5757
38951
10
-9169 -1574 3580 -8579 -7177 -3216 7490 3470 3465 -1197
18005
10
941 7724 2220 -4704 -8374 -8249 7606 9502 612 -9097
28605
10
4836 -2331 -3456 2312 -1574 3134 -670 -204 512 -5504
8463
10
1184 5136 1654 3254 6576 6900 6468 327 179 7114
38613
10
-2152 -1776 -1810 -9046 -6090 -2324 -8716 -6103 -787 -812
-787
3
1 1 1
3
5
5 5 5 3 -1
17
5
-1 -2 5 3 0
7
5
-3 -2 5 -1 3
7
3
-2 2 -1
1
5
5 0 7 -2 3
15
2
-2 -5
-5
3
-1 -3 0
-1
5
2 -1 0 -3 -2
1
4
2 3 0 5
7
5
-5 3 -2 2 5
7
59
8593 5929 3016 -859 4366 -6842 8435 -3910 -2458 -8503 -3612 -9793 -5360 -9791 -362 -7180 727 -6245 -8869 -7316 8214 -7944 7098 3788 -5436 -6626 -1131 -2410 -5647 -7981 263 -5879 8786 709 6489 5316 -4039 4909 -4340 7979 -89 9844 -906 172 -7674 -3371 -6828 9505 3284 5895 3646 6680 -1255 3635 -9547 -5104 -1435 -7222 2244
129433
17
-6170 2363 6202 -9142 7889 779 2843 -5089 2313 -3952 1843 5171 462 -3673 5098 -2519 9565
43749
26
-8668 9705 1798 -1766 9644 3688 8654 -3077 -5462 2274 6739 2732 3635 -4745 -9144 -9175 -7488 -2010 1637 1118 8987 1597 -2873 -5153 -8062 146
60757
51
8237 -7239 -3545 -6059 -5110 4066 -4148 -7641 -5797 -994 963 1144 -2785 -8765 -1216 5410 1508 -6312 -6313 -680 -7657 4579 -6898 7379 2015 -5087 -5417 -6092 3819 -9101 989 -8380 9161 -7519 -9314 -3838 7160 5180 567 -1606 -3842 -9665 -2266 1296 -8417 -3976 7436 -2075 -441 -4565 3313
73781
1
-1
-1
1
1
1
1
-1
-1
1
1
1
1
1
1
1
-1
-1
1
-1
-1
1
1
1
2
-2 1
1
2
3 2
5
2
1 2
3
2
-1 1
1
2
0 -1
-1
2
2 1
3
2
3 0
3
2
0 -1
-1
3
-3 1 -1
1
3
3 -1 1
3
3
1 3 1
5
3
-1 0 1
1
3
-3 -3 -2
-3
3
3 -1 1
3
3
3 -1 1
3
3
-2 -2 1
1
4
0 -1 -3 -4
-1
4
5 3 2 1
11
4
-1 -2 4 -2
3
4
-1 -3 0 -3
-1
4
1 -4 -3 -4
1
4
5 3 3 4
15
4
-1 -3 -1 2
1
4
3 2 -1 -4
5
5
-5 -4 -3 -5 2
-1
5
5 5 1 2 -2
13
5
-2 -1 -5 -1 4
3
5
-5 -5 -4 4 0
-1
5
2 -3 -1 -4 -5
1
5
4 3 4 2 3
13
5
0 -2 -5 3 3
3
5
4 -2 -2 -3 0
1
6
6 7 -1 1 5 -1
19
6
-1 7 2 -3 -4 -5
9
6
0 -1 -3 -5 2 -6
1
6
4 -1 0 3 6 1
13
6
5 3 3 4 4 -3
19
6
0 -3 5 -4 5 -4
7
6
-5 -3 1 -1 -5 -3
1
6
-2 1 3 -2 7 4
15
7
0 7 6 2 7 0 6
21
7
6 -6 -1 -5 7 1 7
21
7
2 3 -5 0 -4 0 -4
5
7
-6 3 -3 -1 -6 -6 -5
3
7
7 6 3 2 4 2 0
21
7
-2 3 -3 4 4 0 -1
11
7
-5 -7 4 0 5 -3 -5
9
7
-3 -5 -4 1 3 -4 -7
3
8
5 2 4 5 7 -2 7 3
33
8
-8 -3 -1 3 -8 -4 -4 4
7
8
-6 -7 -7 -5 -4 -9 -2 -7
-5
8
8 7 6 8 3 4 8 -2
41
8
6 7 0 -6 6 5 4 7
35
8
0 -7 -5 -5 5 -1 -8 -7
5
8
1 -6 -5 7 -3 -4 2 -2
9
8
1 -8 -6 -6 -6 -7 -5 -1
1
9
-3 -1 4 4 8 -8 -5 9 -2
25
9
-9 -1 3 -2 -7 2 -9 -1 -4
5
9
-6 -9 -3 -8 -5 2 -6 0 -5
-1
9
5 4 3 3 6 7 8 5 9
47
9
5 3 9 1 5 2 -3 7 0
31
9
-3 -9 -1 -7 5 6 -4 -6 -6
11
9
-6 -5 6 -5 -2 0 1 2 -9
9
9
8 3 6 1 -3 5 2 9 1
35
10
-6 -4 -7 -1 -9 -10 -10 1 0 -3
1
10
-2 -10 -5 -6 -10 -3 -6 -3 -8 -8
-3
10
8 5 9 2 3 3 -6 1 -1 8
39
10
2 10 -7 6 -1 -1 7 -9 -4 -6
25
10
-10 -2 -2 -1 -10 -7 1 0 -4 -5
1
10
4 3 10 -2 -1 0 10 6 7 0
39
10
-2 6 6 5 0 10 6 7 -1 1
41
10
-10 2 8 -6 -1 -5 1 -10 -10 -1
11

import functools
import copy
import itertools



'''def find_path(graph, encode, s, d, visited, path, paths):
    visited[s] = True
    path.append(s)
    if s == d:
        sumP = sum([encode[p] for p in path])
        if sumP % 2 != 0: paths.add(sumP)
    else:
        for adj in graph:
            if not visited[adj]: find_path(graph, encode, adj, d, visited, path, paths)
    visited[s] = False
    path.pop()



def odd_sum(ls):
    graph = {i:[j for j in range(i, len(ls)) if i != j] for i in range(len(ls))}
    encode = {i:ls[i] for i in range(len(ls))}
    paths = set()
    for s in graph:
        for d in graph:
            if s != d:
                find_path(graph, encode, s, d, {n:False for n in graph}, list(), paths)
    return max(paths)'''



def odd_sum(ls):
    if not len(ls):
        return 0
    else:
        n1 = ls[0] + odd_sum(ls[1:])
        n2 = odd_sum(ls[1:])
        if n1 % 2 != 0 and n2 % 2 != 0: return max(n1, n2)
        elif n1 % 2 != 0 and n2 % 2 == 0: return n1
        elif n1 % 2 == 0 and n2 % 2 != 0: return n2
        else: return -1







if __name__ == '__main__':
    n = int(input())
    ls = [int(i) for i in input().split()]
    print(odd_sum(ls))
