Time travel Problem Description Agent K is one of the greatest agents in a secret organization called Men in Black. Once he needs to finish a mission by traveling through time with the Time machine. The Time machine can take agent K to some point (0…

题目链接: http://acm.hdu.edu.cn/showproblem.php?pid=4418 Time travel Time Limit: 2000/1000 MS (Java/Others)Memory Limit: 32768/32768 K (Java/Others) 问题描述 Agent K is one of the greatest agents in a secret organization called Men in Black. Once he needs to…

ATM Mechine 题目链接: http://acm.hdu.edu.cn/showproblem.php?pid=5781 Description Alice is going to take all her savings out of the ATM(Automatic Teller Machine). Alice forget how many deposit she has, and this strange ATM doesn't support query deposit. T…

wolf5x Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 402    Accepted Submission(s): 248 Special Judge Problem Description There are n grids in a row. The coordinates of grids are numbered fro…

Aeroplane chess Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 1503    Accepted Submission(s): 1025 Problem Description Hzz loves aeroplane chess very much. The chess map contains N+1 grids la…

///题意: /// A,B掷骰子,对于每一次点数大者胜,平为和,A先胜了m次A赢,B先胜了n次B赢. ///p1表示a赢,p2表示b赢,p=1-p1-p2表示平局 ///a赢得概率 比一次p1 两次p0*p1 三次 p0^2*p1,即A赢的概率为p1+p*p1+p^2*p1+...p^n*p1,n->无穷 ///即a_win=p1/(1-p);b_win=p2/(1-p); ///dp[i][j]表示a赢了j次,b赢了i次的概率 ///dp[i][j]=dp[i-1][j]*b_win+dp[…

Card Collector Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 3407    Accepted Submission(s): 1665Special Judge Problem Description In your childhood, do you crazy for collecting the beautiful…

高斯消元求期望!! 将n时间点构成2*(n-1)的环,每一点的期望值为dp[i]=dp[i+1]*p1+dp[i+2]*p2+……+dp[i+m]*pm+1. 这样就可以多个方程,利用高斯消元求解. 代码如下: #include<iostream> #include<stdio.h> #include<algorithm> #include<iomanip> #include<cmath> #include<cstring> #inc…

Time travel http://acm.hdu.edu.cn/showproblem.php?pid=4418 分析: 因为走到最后在折返,可以将区间复制一份,就变成了只往右走,012343210. 写出转移方程: $f[t] = 0$ $f[i] = p_1 \times (f[i +1] + 1) + p_2 \times (f[i +2] + 2) + \cdots$ $ =\sum\limits_{j=1}^{m}p_j \times (f[i + j] + j) $ $= \su…

(转)http://blog.csdn.net/u013081425/article/details/39240021 http://acm.hdu.edu.cn/showproblem.php?pid=4418 读了一遍题后大体明白意思,但有些细节不太确定.就是当它处在i点处,它有1~m步可以走,但他走的方向不确定呢.后来想想这个方向是确定的,就是他走到i点的方向,它会继续朝着这个方向走,直到转向回头. 首先要解决的一个问题是处在i点处,它下一步该到哪个点.为了解决方向不确定的问题,将n个点转…