http://poj.org/problem?id=2398
poj2318的翻版，所不同的是本题所给的线并不排好序的，加一个sort()函数排序即可。（poj2318解题报告）
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<iostream>
#include<algorithm>
using namespace std;
double y1,y2,**p=new double*[1005];
double judge(int j,double x,double y)
{
return (p[j][1]-p[j][0])*(y-y1)-(y2-y1)*(x-p[j][0]);
}
bool cmp(double *a,double *b)
{
return a[0]<b[0];
}
int main()
{
int ans[1005],ans2[1005],i,j,n,m,low,high,mid;
double x,y,x1,x2;
while(scanf("%d",&n),n)
{
memset(ans,0,sizeof(ans));
memset(ans2,0,sizeof(ans2));
scanf("%d%lf%lf%lf%lf",&m,&x1,&y1,&x2,&y2);
for(i=1;i<=n;i++)
{
p[i]=new double[2];
scanf("%lf%lf",&p[i][0],&p[i][1]);
}
p[0]=new double[2];p[n+1]=new double[2];
p[0][0]=x1;p[0][1]=x1;
p[n+1][0]=x2;p[n+1][1]=x2;
sort(p+1,p+n+1,cmp);
for(i=0;i<m;i++)
{
low=0;high=n+1;
mid=(low+high)/2;
scanf("%lf%lf",&x,&y);
if(judge(0,x,y)==0)
mid=0;
else if(judge(n+1,x,y)==0)
mid=n;
else
{
while(low<high)
{
if(judge(mid,x,y)<0)
{
high=mid-1;
mid=(low+high)/2;
}
else
{
low=mid+1;
mid=(low+high)/2;
}
}
if(judge(mid,x,y)<0)
mid--;
}
ans[mid]++;
}
for(i=0;i<=n;i++)
ans2[ans[i]]++;
printf("Box\n");
for(i=1;i<=m;i++)
if(ans2[i])
printf("%d: %d\n",i,ans2[i]);
}
return 0;
}