题意 : 对输入的点极角排序
思路 : 极角排序方法
#include <iostream> #include <cmath> #include <stdio.h> #include <algorithm> using namespace std; struct point { double x,y; }p[50],pp; double cross(point a,point b,point c) { return (a.x-c.x)*(b.y-c.y)-(b.x-c.x)*(a.y-c.y) ; } bool cmp(point a,point b) { int cr = cross(a,b,pp) ;//判断顺时针还是逆时针 if(cr > 0) return true ; else if(cr < 0) return false ; } int main() { int cnt = 0; while (scanf("%lf %lf",&p[cnt].x,&p[cnt].y) != EOF) { ++cnt; } pp.x = pp.y = 0 ; sort(p+1,p+cnt,cmp); for (int i = 0 ; i < cnt ; i++) { cout<<"("<<p[i].x<<","<<p[i].y<<")"<<endl; } return 0; }
时间: 2024-11-09 05:59:39