BZOJ 1935 Tree 园丁的烦恼 [差分][树状数组]

#include<cstdio>
#include<algorithm>
using namespace std;
#define N 500005
#define X 10000005
inline int in(int x=0,char ch=getchar()){while(ch>'9'||ch<'0') ch=getchar();
while(ch>='0'&&ch<='9') x=(x<<3)+(x<<1)+ch-'0',ch=getchar();return x;}
struct Point{int x,y;}p
;
struct Qus{int x,y,f,id;}q[N<<2];
inline bool operator < (const Point &a,const Point &b){return a.x<b.x;}
inline bool operator < (const Qus &a,const Qus &b){return a.x<b.x||(a.x==b.x&&a.y<b.y);}
int ans
;int n,m,cnt;int d[X];
inline void Add(int x){for(;x<X;x+=x&-x) d[x]++;}
inline int Sum(int x,int res=0){for(;x;x-=x&-x) res+=d[x];return res;}
int main(){
n=in(),m=in();int x1,y1,x2,y2;
for(int i=1;i<=n;i++) p[i].x=in()+1,p[i].y=in()+1;
for(int i=1;i<=m;i++){
x1=in()+1,y1=in()+1,x2=in()+1,y2=in()+1;
q[++cnt]=(Qus){x1-1,y1-1,1,i};
q[++cnt]=(Qus){x1-1,y2,-1,i};
q[++cnt]=(Qus){x2,y1-1,-1,i};
q[++cnt]=(Qus){x2,y2,1,i};
}
sort(p+1,p+n+1);sort(q+1,q+cnt+1);
for(int i=1,j=1;i<=cnt;i++){
for(;j<=n&&p[j].x<=q[i].x;j++) Add(p[j].y);
ans[q[i].id]+=Sum(q[i].y)*q[i].f;
}
for(int i=1;i<=m;i++) printf("%d\n",ans[i]);
return 0;
}