注意一个地方，在建立好层次图进行dfs增广时，如果某个点增广不出流量，那么将该点level值置为0，即将它在该层次图中删除，剪枝，否则会超时~
#include <iostream>
#include <cstdio>
#include <cstring>
using namespace std;
const int maxn=1050;
#define inf 10000000
int n,m;
int level[maxn],que[maxn*5];
int head[maxn],lon;
int min(int a,int b)
{
if(a<b) return a;
else return b;
}
struct
{
int next,to,c;
}e[500100];
void edgeini()
{
memset(head,-1,sizeof(head));
lon=-1;
}
void edgemake(int from,int to,int c)
{
e[++lon].c=c;
e[lon].to=to;
e[lon].next=head[from];
head[from]=lon;
}
void make(int from,int to,int c)
{
edgemake(from,to,c);
edgemake(to,from,0);
}
bool makelevel(int s,int t)
{
memset(level,0,sizeof(level));
int front=1,end=0;
que[++end]=s;
level[s]=1;
while(front<=end)
{
int u=que[front++];
if(u==t) return true;
for(int k=head[u];k!=-1;k=e[k].next)
{
int v=e[k].to;
if(!level[v]&&e[k].c)
{
que[++end]=v;
level[v]=level[u]+1;
}
}
}
return false;
}
int dfs(int now,int t,int maxf)
{
if(now==t||maxf==0) return maxf;
int ret=0;
for(int k=head[now];k!=-1;k=e[k].next)
{
int u=e[k].to;
int f;
if(level[u]==level[now]+1&&e[k].c)
{
f=dfs(u,t,min(e[k].c,maxf-ret));
e[k].c-=f;
e[k^1].c+=f;
ret+=f;
if(ret==maxf) return ret;
}
}
if (ret==0) level[now] = 0;
return ret;
}
int maxflow(int s,int t)
{
int ret=0;
while(makelevel(s,t))
{
ret+=dfs(s,t,inf);
}
return ret;
}
int main()
{
int t;
scanf("%d",&t);
int sum=0;
while(t--)
{
edgeini();
int STA,END;
int tot=0;
sum++;
int i,j;
int d=0;
int p,s,e;
scanf("%d%d",&n,&m);
for(i=1;i<=n;i++)
{
scanf("%d%d%d",&p,&s,&e);
tot+=p;
if(e>d) d=e;
make(0,i,p);
for(j=s;j<=e;j++) make(i,j+n,1);
}
STA=0;END=d+n+1;
for(i=1;i<=d;i++) make(i+n,END,m);
int ans=maxflow(STA,END);
printf("Case %d: ",sum);
if(ans==tot) printf("Yes
");
else printf("No
");
printf("
");
}
return 0;
}
#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;
const int maxn=1050;
#define inf 10000000
int n,m;
int level[maxn],que[maxn*5];
int head[maxn],lon;
int a[maxn*2];
int min(int a,int b)
{
if(a<b) return a;
else return b;
}
struct
{
int next,to,c;
}e[500100];
void edgeini()
{
memset(head,-1,sizeof(head));
lon=-1;
}
void edgemake(int from,int to,int c)
{
e[++lon].c=c;
e[lon].to=to;
e[lon].next=head[from];
head[from]=lon;
}
void make(int from,int to,int c)
{
edgemake(from,to,c);
edgemake(to,from,0);
}
bool makelevel(int s,int t)
{
memset(level,0,sizeof(level));
int front=1,end=0;
que[++end]=s;
level[s]=1;
while(front<=end)
{
int u=que[front++];
if(u==t) return true;
for(int k=head[u];k!=-1;k=e[k].next)
{
int v=e[k].to;
if(!level[v]&&e[k].c)
{
que[++end]=v;
level[v]=level[u]+1;
}
}
}
return false;
}
int dfs(int now,int t,int maxf)
{
if(now==t||maxf==0) return maxf;
int ret=0;
for(int k=head[now];k!=-1;k=e[k].next)
{
int u=e[k].to;
int f;
if(level[u]==level[now]+1&&e[k].c)
{
f=dfs(u,t,min(e[k].c,maxf-ret));
e[k].c-=f;
e[k^1].c+=f;
ret+=f;
if(ret==maxf) return ret;
}
}
if (ret==0) level[now] = 0;
return ret;
}
int maxflow(int s,int t)
{
int ret=0;
while(makelevel(s,t))
{
ret+=dfs(s,t,inf);
}
return ret;
}
int main()
{
int t;
while(scanf("%d%d",&n,&m)!=EOF)
{
edgeini();
int STA,END;
int tot=0;
int i,j;
int si[maxn],ni,ei[maxn],ti;
int cnt=0;
STA=0;
for(i=1;i<=n;i++)
{
scanf("%d%d%d%d",&si[i],&ni,&ei[i],&ti);
make(STA,i,ni*ti);
tot+=ni*ti;
a[cnt++]=si[i];
a[cnt++]=ei[i];
}
sort(a,a+cnt);
j=1;
for(i=1;i<cnt;i++)
if(a[i]>a[i-1])
a[j++]=a[i];
cnt=j;
END=n+cnt;
for(i=1;i<=cnt-1;i++)
{
make(n+i,END,m*(a[i]-a[i-1]));
for(j=1;j<=n;j++)
if(a[i-1]>=si[j]&&a[i]<=ei[j])
make(j,n+i,inf);
}
int ans=maxflow(STA,END);
if(ans==tot) printf("Yes
");
else printf("No
");
}
return 0;
}