hdu 4429 Split the Rectangle

读懂题意之后就是简单的暴力找一个最小的矩形去包围这两个点，然后把这个矩形内部的点全部去掉，就可以得出答案。

#include <iostream>#include <cstdio>#include <cstring>using namespace std;const int maxn=2e3+9,inf=1e9;int n,q;int lonl,lonr;struct{    int x1,x2,y1,y2;}line[maxn];struct{    int x1,x2,y1,y2;}rec[maxn<<1];void push(int x1,int x2,int y1,int y2){    rec[++lonr].x1=x1;    rec[lonr].x2=x2;    rec[lonr].y1=y1;    rec[lonr].y2=y2;}void pushline(int x1,int x2,int y1,int y2){    line[++lonl].x1=x1;    line[lonl].x2=x2;    line[lonl].y1=y1;    line[lonl].y2=y2;}void insert(int x1,int x2,int y1,int y2){    int up=inf,down=-inf;    if(x1==x2)    {        for(int i=1;i<=lonl;i++)        {            if(line[i].y1<=y1&&line[i].y2>=y2)            {                if(line[i].x1>x1&&line[i].x1<up) up=line[i].x1;                if(line[i].x1<x1&&line[i].x1>down) down=line[i].x1;            }        }        push(down,x1,y1,y2);        push(x1,up,y1,y2);    }    else    {        for(int i=1;i<=lonl;i++)        {            if(line[i].x1<=x1&&line[i].x2>=x2)            {                if(line[i].y1>y1&&line[i].y1<up) up=line[i].y1;                if(line[i].y1<y1&&line[i].y1>down) down=line[i].y1;            }        }        push(x1,x2,down,y1);        push(x1,x2,y1,up);    }}void work(int &x1,int &x2,int &y1,int &y2){    if(x1>x2) swap(x1,x2);    if(y1>y2) swap(y1,y2);}bool chk(int xd,int xu,int yd,int yu,int t){    bool flag=false;    if(line[t].x1<xd) return false;    else if(line[t].x1>xd&&line[t].x1<xu) flag=true;    if(line[t].x2>xu) return false;    else if(line[t].x2>xd&&line[t].x2<xu) flag=true;    if(line[t].y1<yd) return false;    else if(line[t].y1>yd&&line[t].y1<yu) flag=true;    if(line[t].y2>yu) return false;    else if(line[t].y2>yd&&line[t].y2<yu) flag=true;    return flag;}void solve(int x1,int x2,int y1,int y2){    int xd,xu,yd,yu;    int now=inf;    for(int i=1;i<=lonr;i++)    if(rec[i].x1<=x1&&rec[i].x2>=x2&&rec[i].y1<=y1&&rec[i].y2>=y2)    {        int tmp=rec[i].x2+rec[i].y2-rec[i].x1-rec[i].y1;        if(now>tmp)        {            xd=rec[i].x1;            xu=rec[i].x2;            yd=rec[i].y1;            yu=rec[i].y2;            now=tmp;        }    }    int ans=n+1;    for(int i=1;i<=lonl;i++)    {        if(chk(xd,xu,yd,yu,i))        ans--;    }    cout<<ans<<endl;}int main(){//    freopen("in.txt","r",stdin);    int x1,x2,y1,y2;    while(scanf("%d%d%d%d",&x1,&y1,&x2,&y2)!=EOF)    {        lonl=lonr=0;        work(x1,x2,y1,y2);        push(x1,x2,y1,y2);        pushline(x1,x1,y1,y2);        pushline(x2,x2,y1,y2);        pushline(x1,x2,y1,y1);        pushline(x1,x2,y2,y2);        scanf("%d%d",&n,&q);        for(int i=1;i<=n;i++)        {            scanf("%d%d%d%d",&x1,&y1,&x2,&y2);            work(x1,x2,y1,y2);            insert(x1,x2,y1,y2);            pushline(x1,x2,y1,y2);        }        for(int i=1;i<=q;i++)        {            scanf("%d%d%d%d",&x1,&y1,&x2,&y2);            work(x1,x2,y1,y2);            solve(x1,x2,y1,y2);        }    }    return 0;}