BZOJ4276 : [ONTAK2015]Bajtman i Okrągły Robin

#include<cstdio>
const int inf=~0U>>2,N=15010,M=1000000;
int n,i,A,B,C,ans,cl
,cr
,tot=1;unsigned short l,r;
int u[M],v[M],c[M],co[M],nxt[M],t=1,S,T=1,q[65536],g
,f
,d
;bool in
;
inline void add(int x,int y,int z,int zo){
u[++t]=x;v[t]=y;c[t]=z;co[t]=zo;nxt[t]=g[x];g[x]=t;
u[++t]=y;v[t]=x;c[t]=0;co[t]=-zo;nxt[t]=g[y];g[y]=t;
}
inline bool spfa(){
int x,i;
for(i=1;i<=tot;i++)d[i]=-inf,in[i]=0;
d[S]=0;in[S]=1;q[l=r=0]=S;
while(l!=r+1){
int x=q[l++];
if(x==T)continue;
for(i=g[x];i;i=nxt[i])if(c[i]&&co[i]+d[x]>d[v[i]]){
int y=v[i];
d[y]=co[i]+d[x];f[y]=i;
if(!in[y]){
in[y]=1;
if(d[y]>d[q[l]])q[--l]=y;else q[++r]=y;
}
}
in[x]=0;
}
return d[T]>0;
}
int build(int a,int b){
int x=++tot;
if(a==b)return add(S,x,1,0),x;
int mid=(a+b)>>1;
add(cl[x]=build(a,mid),x,inf,0);
add(cr[x]=build(mid+1,b),x,inf,0);
return x;
}
void addedge(int x,int a,int b){
if(A<=a&&b<=B){add(x,tot,1,0);return;}
int mid=(a+b)>>1;
if(A<=mid)addedge(cl[x],a,mid);
if(B>mid)addedge(cr[x],mid+1,b);
}
int main(){
build(1,4999);
for(scanf("%d",&n);n--;addedge(2,1,4999))scanf("%d%d%d",&A,&B,&C),add(++tot,T,1,C),B--;
while(spfa())for(ans+=d[T],i=T;i!=S;i=u[f[i]])c[f[i]]--,c[f[i]^1]++;
return printf("%d",ans),0;
}