POJ 2593

 1 #include <iostream>
 2 #include <stdio.h>
 3 using namespace std;
 4 int cmp ( const void *a , const void *b )
 5 {
 6     return *(int *)b - *(int *)a;
 7 }
 8 int main()
 9 {
10     int sum,n,flag,i,a[100010];
11     while (1)
12     {
13         sum=0;
14         flag=0;
15         scanf("%d",&n);
16         if (n==0)
17             break;
18         for (i=0;i<n;i++)
19         {
20             scanf("%d",&a[i]);
21             if (a[i]>0)
22             {
23                 flag++;
24                 sum+=a[i];
25             }
26         }
27         if (flag==0||flag==1)
28         {
29             qsort(a,n,sizeof(a[0]),cmp);
30             printf("%d\n",a[0]+a[1]);
31         }
32         else printf("%d\n",sum);
33     }
34     return 0;
35 }