OJ-Problems-Source/HDOJ/3178_autoAC.cpp

37 lines
818 B
C++

#include <cstdio>
#include <iostream>
using namespace std;
#define N 1005
#define L 0.0000001
double a[N];
double b[N];
int main()
{
int t;
scanf("%d",&t);
while(t--)
{
int n;
scanf("%d",&n);
int i = 0;
for(i = 1; i <= n; i++)
scanf("%lf%lf",&a[i],&b[i]);
int p1,p2;
scanf("%d%d",&p1,&p2);
double x1 = a[p2] - a[p1];
double y1 = b[p2] - b[p1];
for(i = 1; i <= n; i++)
{
double x2 = a[i] - a[p1];
double y2 = b[i] - b[p1];
double sum = x1*y2 - x2*y1;
if(sum < -L)
printf("Right\n");
else if(sum > L)
printf("Left\n");
else printf("On\n");
}
}
return 0;
}