思路：
（from mhr） //By SiriusRen#include#include #include #include using namespace std;#define N 444#define M 2222int first[N],next[M],v[M],edge[M],cost[M],s[N],top,tot,ans,T;int cases,n,K,xx[N],yy[N],zz[N],vis[N],d[N],with[N],minn[N];void Add(int x,int y,int C,int E){ edge[tot]=E,cost[tot]=C,v[tot]=y,next[tot]=first[x],first[x]=tot++;}void add(int x,int y,int C,int E){Add(x,y,C,E),Add(y,x,-C,0);}bool tell(){ memset(vis,0,sizeof(vis)),memset(d,0x3f,sizeof(d)); memset(with,0,sizeof(with)),memset(minn,0x3f,sizeof(minn)); queue q;q.push(0);d[0]=0; while(!q.empty()){ int t=q.front();q.pop();vis[t]=0; for(int i=first[t];~i;i=next[i]) if(d[v[i]]>d[t]+cost[i]&&edge[i]>0){ d[v[i]]=d[t]+cost[i],minn[v[i]]=min(minn[t],edge[i]),with[v[i]]=i; if(!vis[v[i]])vis[v[i]]=1,q.push(v[i]); } }return d[T]!=0x3f3f3f3f;}int zeng(){ for(int i=T;i;i=v[with[i]^1]) edge[with[i]]-=minn[T],edge[with[i]^1]+=minn[T]; return d[T];}int main(){ scanf("%d",&cases); while(cases--){ memset(first,-1,sizeof(first)),tot=top=ans=0; scanf("%d%d",&n,&K); for(int i=1;i<=n;i++){ scanf("%d%d%d",&xx[i],&yy[i],&zz[i]); s[++top]=xx[i],s[++top]=yy[i]; } sort(s+1,s+1+top),add(0,1,0,K); T=unique(s+1,s+1+top)-s; for(int i=1;i<=n;i++){ int tx=lower_bound(s+1,s+T,xx[i])-s,ty=lower_bound(s+1,s+T,yy[i])-s; add(tx,ty,-zz[i],1); } for(int i=0;i
