[BZOJ3262]陌上花开(CDQ分治)
经典的三位偏序经(mo)典(ban)题，
一维排序，二维CDQ分治，3维BIT
Code
#include <cstdio>
#include <algorithm>
#define lowbit(x) ((x)&(-x))
#define N 100010
using namespace std;
inline int read(){
int x=0,f=1;char ch=getchar();
while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
return x*f;
}
struct flower{
int a,b,c,w,s;
flower(){a=b=c=w=s=0;}
friend bool operator <(flower x,flower y){
return (x.a==y.a&&x.b==y.b)?(x.c<y.c):((x.a==y.a)?x.b<y.b:x.a<y.a);
}
friend bool operator ==(flower x,flower y){
return (x.a==y.a&&x.b==y.b&&x.c==y.c);
}
void rd(){a=read(),b=read(),c=read(),w=1;}
}A[N],tmp[N];
int n,mx,na,T[N*2],Ans[N];
inline void Init(){
n=read(),mx=read();
for(int i=1;i<=n;A[i++].rd());
sort(A+1,A+n+1);
int p=1;
for(int i=2;i<=n;++i) if(A[i]==A[p]) A[p].w++;else A[++p]=A[i];//去重
na=n,n=p;
}
void add(int x,int v){for(;x<=mx;x+=lowbit(x)) T[x]+=v;}
int sum(int x){int r=0;for(;x;x-=lowbit(x)) r+=T[x];return r;}
inline void solve(int l,int r){
if(l==r) return;
int m=(l+r)>>1;
solve(l,m),solve(m+1,r);
int p=l,q=m+1,cnt=l;
while(p<=m||q<=r)
if(q>r||(p<=m&&A[p].b<=A[q].b)) add(A[p].c,A[p].w),tmp[cnt++]=A[p++];
else A[q].s+=sum(A[q].c),tmp[cnt++]=A[q++];
for(int i=l;i<=m;++i) add(A[i].c,-A[i].w);//清空BIT
for(int i=l;i<=r;++i) A[i]=tmp[i];
}
int main(){
Init();
solve(1,n);
for(int i=1;i<=n;++i) Ans[A[i].s+A[i].w-1]+=A[i].w;
for(int i=0;i<na;printf("%d\n",Ans[i++]));
return 0;
}
