[SDOI2009][BZOJ1877] 晨跑

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 #include<cstdlib>
 5 #include<algorithm>
 6 #include<cmath>
 7 #include<vector>
 8 #include<queue>
 9 #define inf 1000007
10 #define MOD 500
11 using namespace std;
12 int n,m,x,y,z,cnt,ans1,ans2,dis[501],path[501],head[501],q[501];
13 bool v[501];
14 int next[100000],from[100000],list[100000],flow[100000],cost[100000];
15 void insert(int x,int y,int w,int z)
16 {
17     next[++cnt]=head[x];
18     head[x]=cnt;
19     from[cnt]=x;
20     list[cnt]=y;
21     flow[cnt]=w;
22     cost[cnt]=z;
23 }
24 bool spfa()
25 {
26     int t=0,w=1,x;
27     for (int i=1;i<=2*n;i++) dis[i]=inf;
28     memset(v,0,sizeof(v));
29     q[1]=1; dis[1]=0; v[1]=1;
30     while (t!=w)
31     {
32         t=(t+1)%MOD;
33         x=q[t];
34         for (int i=head[x];i;i=next[i])
35             if (flow[i]>0&&dis[x]+cost[i]<dis[list[i]])
36             {
37                 dis[list[i]]=dis[x]+cost[i];
38                 path[list[i]]=i;
39                 if (!v[list[i]])
40                 {
41                     v[list[i]]=1;
42                     w=(w+1)%MOD;
43                     q[w]=list[i];
44                 }
45             }
46         v[x]=0;
47     }
48     return dis[2*n]!=inf;
49 }
50 void mcf()
51 {
52     int x=inf,i;
53     i=path[2*n];
54     while (i)
55     {
56         x=min(x,flow[i]);
57         i=path[from[i]];
58     }
59     ans1++;
60     i=path[2*n];
61     while (i)
62     {
63         ans2+=x*cost[i];
64         flow[i]-=x;
65         flow[i^1]+=x;
66         i=path[from[i]];
67     }
68 }
69 int main()
70 {
71     scanf("%d%d",&n,&m);
72     cnt=1;
73     for (int i=1;i<=m;i++)
74     {
75         scanf("%d%d%d",&x,&y,&z);
76         insert(x+n,y,1,z);
77         insert(y,x+n,0,-z);
78     }
79     for (int i=2;i<n;i++)
80     {
81         insert(i,i+n,1,0);
82         insert(i+n,i,0,0);
83     }
84     insert(1,n+1,inf,0);
85     insert(n+1,1,0,0);
86     insert(n,2*n,inf,0);
87     insert(2*n,n,0,0);
88     while (spfa()) mcf();
89     printf("%d %d",ans1,ans2);
90     return 0;
91 }