HDU 4647 Another Graph Game(贪心)

思路题。看的题解。
 1 #include <cstdio>
 2 #include <string>
 3 #include <cstring>
 4 #include <algorithm>
 5 using namespace std;
 6 #define LL __int64
 7 LL p[100001];
 8 int main()
 9 {
10     int i,n,m,sv,ev,w;
11     while(scanf("%d%d",&n,&m)!=EOF)
12     {
13         memset(p,0,sizeof(p));
14         for(i = 1;i <= n;i ++)
15         {
16             scanf("%I64d",&p[i]);
17             p[i] = p[i]*2;
18         }
19         for(i = 0;i < m;i ++)
20         {
21             scanf("%d%d%d",&sv,&ev,&w);
22             p[sv] += w;
23             p[ev] += w;
24         }
25         sort(p+1,p+n+1);
26         LL ans = 0;
27         for(i = 1;i <= n;i ++)
28         {
29             if(i%2)
30             ans -= p[i];
31             else
32             ans += p[i];
33         }
34         printf("%I64d
",ans/2);
35     }
36     return 0;
37 }