#include<iostream>#include<cmath>#include<complex>#include<algorithm>#define max(a,b) (a)>(b)?(a):(b)#define min(a,b) (a)<(b)?(a):(b)#define EPS 1e-8using namespace std;struct point { double x,y; };point convex[50];double cross(const point &p1, const point &p2, const point &q1, const point &q2){ return (q2.y - q1.y)*(p2.x - p1.x) - (q2.x - q1.x)*(p2.y - p1.y); }bool cmp(const point &a, const point &b){ point origin; origin.x = origin.y = 0; return cross(origin,b,origin,a) < 0;}int main(){ int cnt = 0; while (scanf("%lf%lf",&convex[cnt].x,&convex[cnt].y) != EOF) { ++cnt; } sort(convex+1,convex+cnt,cmp); for (int i(0); i<cnt; ++i) { cout<<"("<<convex[i].x<<","<<convex[i].y<<")"<<endl; } return 0; }
