HDU 4647 Another Graph Game(贪心)

题目链接

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\n",ans/2);

35     }

36     return 0;

37 }