poj3680 Intervals (费用流)

 1 #include<cstring>
 2 #include<cstdio>
 3 #include<algorithm>
 4 #include<queue>
 5 #define CLR(a,x) memset(a,x,sizeof(a))
 6 #define MP make_pair
 7 using namespace std;
 8 typedef long long ll;
 9 typedef unsigned long long ull;
10 typedef pair<int,int> pa;
11 const int maxn=205,maxp=410,inf=1e9;
12 
13 inline ll rd(){
14     ll x=0;char c=getchar();int neg=1;
15     while(c<‘0‘||c>‘9‘){if(c==‘-‘) neg=-1;c=getchar();}
16     while(c>=‘0‘&&c<=‘9‘) x=x*10+c-‘0‘,c=getchar();
17     return x*neg;
18 }
19 
20 int l[maxn],r[maxn],w[maxn],N,M,K,tmp[maxp],S=405,T=406;
21 struct Edge{
22     int b,l,ne,c;
23 }eg[maxp*3];
24 int egh[maxp],ect=1;
25 int dis[maxp],fae[maxp];
26 bool flag[maxp];
27 
28 inline void adeg(int a,int b,int c,int l){
29     // printf("~%d %d %d %d\n",a,b,c,l);
30     eg[++ect].b=b,eg[ect].l=l,eg[ect].c=c,eg[ect].ne=egh[a],egh[a]=ect;
31     eg[++ect].b=a,eg[ect].l=0,eg[ect].c=-c,eg[ect].ne=egh[b],egh[b]=ect;
32 }
33 
34 queue<int> q;
35 inline bool spfa(){
36     CLR(dis,-1);dis[S]=0;
37     CLR(fae,0);q.push(S);
38     while(!q.empty()){
39         int p=q.front();q.pop();
40         // printf("~%d %d\n",p,dis[S]);
41         flag[p]=0;
42         for(int i=egh[p];i;i=eg[i].ne){
43             int b=eg[i].b;if(!eg[i].l) continue;
44             // printf("!!%d %d %d\n",b,eg[i].c,eg[i].l);
45             if(dis[b]<dis[p]+eg[i].c){
46                 dis[b]=dis[p]+eg[i].c;
47                 fae[b]=i;
48                 if(!flag[b]) q.push(b),flag[b]=1;
49             }
50         }
51     }return dis[T]>=0;
52 }
53 
54 int main(){
55     //freopen("","r",stdin);
56     int i,j,k;
57     for(int t=rd();t;t--){
58         N=rd(),K=rd();
59         for(i=1;i<=N;i++){
60             tmp[i]=l[i]=rd(),tmp[i+N]=r[i]=rd(),w[i]=rd();
61         }sort(tmp+1,tmp+N+N+1);
62         int M=unique(tmp+1,tmp+N+N+1)-tmp-1;
63         CLR(egh,0);ect=1;
64         for(i=1;i<=N;i++){
65             l[i]=lower_bound(tmp+1,tmp+M+1,l[i])-tmp;
66             r[i]=lower_bound(tmp+1,tmp+M+1,r[i])-tmp;
67             adeg(l[i],r[i],w[i],1);
68         }
69         for(i=1;i<M;i++){
70             adeg(i,i+1,0,inf);
71         }adeg(M,T,0,K);adeg(S,1,0,K);
72         int ans=0;
73         while(spfa()){
74             int mi=inf;
75             for(i=T;i;i=eg[fae[i]^1].b){
76                 if(fae[i]) mi=min(mi,eg[fae[i]].l);
77             }
78             for(i=T;i;i=eg[fae[i]^1].b){
79                 eg[fae[i]].l-=mi,eg[fae[i]^1].l+=mi;
80             }
81             ans+=mi*dis[T];
82         }
83         printf("%d\n",ans);
84     }
85     return 0;
86 }