HDU-4647 Another Graph Game 贪心,博弈

  题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=4647

  注意这题两人的决策是想要使得自己的分数与对方的差值最大。。

  注意到数据范围,显然是贪心之类的,如果没有变那么很简单,如果有边,那么我们进行拆边,把边的权值的一半加到所连的点上。然后排个序贪心。。

 1 //STATUS:C++_AC_218MS_1020KB
 2 #include <functional>
 3 #include <algorithm>
 4 #include <iostream>
 5 //#include <ext/rope>
 6 #include <fstream>
 7 #include <sstream>
 8 #include <iomanip>
 9 #include <numeric>
10 #include <cstring>
11 #include <cassert>
12 #include <cstdio>
13 #include <string>
14 #include <vector>
15 #include <bitset>
16 #include <queue>
17 #include <stack>
18 #include <cmath>
19 #include <ctime>
20 #include <list>
21 #include <set>
22 #include <map>
23 using namespace std;
24 //#pragma comment(linker,"/STACK:102400000,102400000")
25 //using namespace __gnu_cxx;
26 //define
27 #define pii pair<int,int>
28 #define mem(a,b) memset(a,b,sizeof(a))
29 #define lson l,mid,rt<<1
30 #define rson mid+1,r,rt<<1|1
31 #define PI acos(-1.0)
32 //typedef
33 typedef __int64 LL;
34 typedef unsigned __int64 ULL;
35 //const
36 const int N=100010;
37 const int INF=0x3f3f3f3f;
38 const int MOD= 1000000007,STA=8000010;
39 const LL LNF=1LL<<55;
40 const double EPS=1e-9;
41 const double OO=1e30;
42 const int dx[4]={-1,0,1,0};
43 const int dy[4]={0,1,0,-1};
44 const int day[13]={0,31,28,31,30,31,30,31,31,30,31,30,31};
45 //Daily Use ...
46 inline int sign(double x){return (x>EPS)-(x<-EPS);}
47 template<class T> T gcd(T a,T b){return b?gcd(b,a%b):a;}
48 template<class T> T lcm(T a,T b){return a/gcd(a,b)*b;}
49 template<class T> inline T lcm(T a,T b,T d){return a/d*b;}
50 template<class T> inline T Min(T a,T b){return a<b?a:b;}
51 template<class T> inline T Max(T a,T b){return a>b?a:b;}
52 template<class T> inline T Min(T a,T b,T c){return min(min(a, b),c);}
53 template<class T> inline T Max(T a,T b,T c){return max(max(a, b),c);}
54 template<class T> inline T Min(T a,T b,T c,T d){return min(min(a, b),min(c,d));}
55 template<class T> inline T Max(T a,T b,T c,T d){return max(max(a, b),max(c,d));}
56 //End
57 
58 double v[N];
59 int n,m;
60 
61 int main(){
62  //   freopen("in.txt","r",stdin);
63     int i,j,a,b;
64     double c,ans;
65     while(~scanf("%d%d",&n,&m))
66     {
67         for(i=1;i<=n;i++){
68             scanf("%lf",&v[i]);
69         }
70         for(i=0;i<m;i++){
71             scanf("%d%d%lf",&a,&b,&c);
72             v[a]+=c/2;
73             v[b]+=c/2;
74         }
75         sort(v+1,v+n+1);
76         ans=0;
77         for(i=n;i>=0;i-=2){
78             ans+=v[i]-v[i-1];
79         }
80 
81         printf("%.0f
",ans);
82     }
83     return 0;
84 }