#include #include #include #include using namespace std; const int N=520; int n,m,ans=-1; int Connect[N][N]; struct Point { int x,y; Point() {} Point(int _x,int _y):x(_x),y(_y) {} Point operator - (const Point &p)const //重载向量减法 { return Point(x-p.x,y-p.y); } } bear[N],house[N]; int CrossProduct(Point A,Point B) //求向量A,B的叉积,即A x B { return (A.x*B.y)-(B.x*A.y); } int main() { #ifdef LOCAL freopen("in.txt","r",stdin); #endif while(~scanf("%d",&n)) { //初始化操作 ans=-1; memset(Connect,0,sizeof(Connect)); for(int i=0; i