Content 有一天,小 V 突然忘记了他在 Codehorses 的网站上的密码.但是他有所有网站上的 \(n\) 个密码 \(\{s_i\}_{i=1}^n\),所以他开始一个一个试.他会先从长度最小的密码开始试,如果有多个长度相等的密码就等概率随机选一个,并且他不会再去试已经试过的密码.输入密码需要 \(1\) 秒,如果连续输错 \(k\) 次密码就需要再等 \(5\) 秒才能重新开始试.已知他的密码是一个字符串 \(t\).求最好情况和最坏情况下他试密码需要的时间. 数据范围:\(1\…

B. Passwords 题目连接: http://codeforces.com/contest/721/problem/B Description Vanya is managed to enter his favourite site Codehorses. Vanya uses n distinct passwords for sites at all, however he can't remember which one exactly he specified during Code…

题目链接:http://codeforces.com/contest/721/problem/B B. Passwords time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Vanya is managed to enter his favourite site Codehorses. Vanya uses n distinct…

time limit per test2 seconds memory limit per test256 megabytes inputstandard input outputstandard output Vanya is managed to enter his favourite site Codehorses. Vanya uses n distinct passwords for sites at all, however he can't remember which one e…

D. Secret Passwords One unknown hacker wants to get the admin's password of AtForces testing system, to get problems from the next contest. To achieve that, he sneaked into the administrator's office and stole a piece of paper with a list of n passwo…

题目 On another floor of the A.R.C. Markland-N, the young man Simon "Xenon" Jackson, takes a break after finishing his project early (as always). Having a lot of free time, he decides to put on his legendary hacker "X" instinct and fight…

我要举报本次校赛出题人的消极出题!!! 官方题解请戳:http://3.scnuacm2015.sinaapp.com/?p=89(其实就是一堆代码没有题解) A. 树链剖分数据结构板题 题目大意:我没看,看不懂. 基本思路:我不会. 参考代码:找Oyk老师和Czj老师去. B. The background of water problem 题目大意(大写加粗的水题):给定$N$个学生和他们$K$个科目的成绩$S_i$,再给出各科目$K_i$的权重顺序$Q_i$,求排名之后,拥有id为$X$的…

以下代码为了阅读方便,省去以下头文件: #include <iostream> #include <stdio.h> #include <math.h> #include <string.h> #include <time.h> #include <stdlib.h> #include <string> #include <bitset> #include <vector> #include <…

2561: 最小生成树(题解) Time Limit: 10 Sec  Memory Limit: 128 MBSubmit: 1628  Solved: 786 传送门:http://www.lydsy.com/JudgeOnline/problem.php?id=2561 Description 给定一个边带正权的连通无向图G=(V,E),其中N=|V|,M=|E|,N个点从1到N依次编号,给定三个正整数u,v,和L (u≠v),假设现在加入一条边权为L的边(u,v),那么需要删掉最少多少条…

Problems     # Name     A Infinite Sequence standard input/output 1 s, 256 MB    x3509 B Restoring Painting standard input/output 1 s, 256 MB    x2519 C Money Transfers standard input/output 1 s, 256 MB    x724 D Tree Construction standard input/outp…