poj 3680 Intervals 费用流

#include <stdio.h>
#include <iostream>
#include <string.h>
#include <algorithm>
using namespace std;
const int MAXN=40000;
const int MAXE=20000000;
const int inf=1<<30;
int head[MAXN],s,t,cnt,ans;
int d[MAXN],pre[MAXN];
bool vis[MAXN];
int q[MAXE];
int le[210],ri[210],fee[210];
int a[500],b[500];
int pos;
struct Edge
{
    int u,v,c,w,next;
}edge[MAXE];

void addedge(int u,int v,int w,int c)
{
    edge[cnt].u=u;
    edge[cnt].v=v;
    edge[cnt].w=w;
    edge[cnt].c=c;
    edge[cnt].next=head[u];
    head[u]=cnt++;
    edge[cnt].v=u;
    edge[cnt].u=v;
    edge[cnt].w=-w;
    edge[cnt].c=0;
    edge[cnt].next=head[v];
    head[v]=cnt++;
}

int SPFA()
{
    int l,r;
    memset(pre,-1,sizeof(pre));
    memset(vis,0,sizeof(vis));
    for(int i=0;i<=t;i++) d[i]=inf;
    d[s]=0;
    l=0;r=0;
    q[r++]=s;
    vis[s]=1;
    while(l<r)
    {
        int u=q[l++];
        vis[u]=0;
        for(int j=head[u];j!=-1;j=edge[j].next)
        {
            int v=edge[j].v;
            if(edge[j].c>0&&d[u]+edge[j].w<d[v])
            {
                d[v]=d[u]+edge[j].w;
                pre[v]=j;
                if(!vis[v])
                {
                    vis[v]=1;
                    q[r++]=v;
                }
            }
        }
    }
    if(d[t]==inf)
        return 0;
    return 1;
}

void MCMF()
{
    int flow=0;
    while(SPFA())
    {
        int u=t;
        int mini=inf;
        while(u!=s)
        {
            if(edge[pre[u]].c<mini)
                mini=edge[pre[u]].c;
                u=edge[pre[u]].u;
        }
        flow+=mini;
        u=t;
        ans+=d[t]*mini;
        while(u!=s)
        {
            edge[pre[u]].c-=mini;
            edge[pre[u]^1].c+=mini;
            u=edge[pre[u]].u;
        }
    }
}
int bin(int u)
{
    int l=1,r=pos,m=(l+r)/2;
    while(l<=r)
    {
        m=(l+r)/2;
        if(u==b[m]) return m;
        else if(u>b[m]) l=m+1;
        else if(u<b[m]) r=m-1;
    }
}
int main()
{
    int n,k;
    int cas;
    int i,j;
    scanf("%d",&cas);
    while(cas--)
    {
        scanf("%d%d",&n,&k);
		cnt=0;
		int now=0;
		for(i=1;i<=n;i++)
		{
		    scanf("%d%d%d",&le[i],&ri[i],&fee[i]);
		    a[now++]=le[i];
		    a[now++]=ri[i];
		}
		sort(a,a+now);
		b[1]=a[0];
		pos=1;
		for(i=1;i<now;i++)
		    if(a[i]!=b[pos])
                b[++pos]=a[i];
        //for(i=1;i<=pos;i++)printf("%d ",b[i]);
        //printf("
");
        s=0;t=pos+1;  //printf("          %d %d
",s,t);
        for(i=0;i<=t;i++)
            head[i]=-1;
        for(i=1;i<=n;i++)
        {
            int u,v;
            u=bin(le[i]);
            v=bin(ri[i]);
            //printf("%d %d
",u,v);
            addedge(u,v,-fee[i],1);
        }
        for(i=0;i<t;i++)
            addedge(i,i+1,0,k);

        ans=0;
        MCMF();
        printf("%d
",-ans);
    }
    return 0;
}