摘要: 题意: 给个有向图,每个节点等概率转移到它的后继节点,现在问一些节点的期望访问次数; 思路: 对于一个点v,Ev=Ea/d[a]+Eb/d[b]+Ec/d[c];a,b,c是v的前驱节点; 然后按这个列出方程,进行高斯约旦消元,然后判断是否可达和是否为0; 代码是白书上的; AC代码: 阅读全文
posted @ 2016-09-05 22:41 LittlePointer 阅读(281) 评论(0) 推荐(0)
摘要: 题目链接: C. Riding in a Lift time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output time limit per 阅读全文
posted @ 2016-09-05 22:33 LittlePointer 阅读(199) 评论(0) 推荐(0)
摘要: 题目链接: B. Long Jumps time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output time limit per test 1 阅读全文
posted @ 2016-09-05 22:25 LittlePointer 阅读(224) 评论(0) 推荐(0)
摘要: 题目链接: A. Exams time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output time limit per test 1 seco 阅读全文
posted @ 2016-09-05 22:18 LittlePointer 阅读(353) 评论(0) 推荐(0)