摘要：
https://www.xht37.com/%e8%ae%a1%e7%ae%97%e5%87%a0%e4%bd%95 %e5%ad%a6%e4%b9%a0%e7%ac%94%e8%ae%b0/ https://www.cnblogs.com/nietzsche oier/p/8798540.html 阅读全文
摘要：
```#include#define ld long double#define ll long longusing namespace std;const ld eps=1e-6;const int N=5e5+7;struct P{ ld x,y; inline P() {} inline P(ld x,ld y):x(x),y(y) {} inline P &operator += (P o... 阅读全文