摘要：第二弾が始まる！ codechef problems 第二弹 一、Backup Functions 题面 One unavoidable problem with running a restaurant is that occasionally a menu item cannot be prep 阅读全文

摘要：Description 在xoy直角坐标平面上有n条直线L1,L2,...Ln,若在y值为正无穷大处往下看,能见到Li的某个子线段,则称Li为 可见的,否则Li为被覆盖的. 例如,对于直线: L1:y=x; L2:y=-x; L3:y=0 则L1和L2是可见的,L3是被覆盖的. 给出n条直线,表示成 阅读全文

摘要：Description Once upon a time there was a greedy King who ordered his chief Architect to build a wall around the King's castle. The King was so greedy, 阅读全文