摘要: "bzoj 2190" 显然 以C菌为原点构建坐标系 当横纵坐标(a,b)不互质时,斜率a/b与a/gcd(a,b)和b/gcd(a,b)斜率相等,那么一定会被(a/gcd(a,b),b/gcd(a,b))挡住 那就是求$\sum_{i=1}^{n}\sum_{j=1}^{n} gcd(i,j)=1 阅读全文
posted @ 2018-02-02 21:48 zzzzx 阅读(189) 评论(0) 推荐(0)
摘要: "bzoj1924" tarjan后dp 常规操作求最长路 include include include include define LL long long const int maxn = 5000007; inline int read() { int x=0,f=1; char c=ge 阅读全文
posted @ 2018-02-02 21:31 zzzzx 阅读(218) 评论(0) 推荐(0)