题意 抄袭自https://www.cnblogs.com/Paul-Guderian/p/7624039.html  多组输入n,m,l,r.表示在一个环上有n个格子.接下来输入m个w表示连续的一段命令,每个w表示机器人沿顺时针或者逆时针方向前进w格,已知机器人是从1号点出发的,输出最后机器人停在环上[l,r]区间的概率.n(1≤n≤200) ,m(0≤m≤1,000,000). Sol 无脑概率dp $f[i][j]$表示第$i$轮,在$j$位置的概率 转移的时候枚举下一轮往哪儿走 最后把$…

题目 /*********************复制来的大致题意********************** 有N个数字,M个操作, 区间L, R. 然后问经过M个操作后落在[L, R]的概率. *******************************************************/ //自己做,错掉了,然后参考了别人的解法,说是要 概率dp //概率模拟题,一定要用概率来模拟, //因为数据很大,可能超了__int64, //模拟方式用dp[2][], 0表示前一个状…

Robot Time Limit: 8000/4000 MS (Java/Others)    Memory Limit: 102400/102400 K (Java/Others)Total Submission(s): 779    Accepted Submission(s): 304 Problem Description Michael has a telecontrol robot. One day he put the robot on a loop with n cells. T…

暴力DP求解太卡时间了...........写挫一点就跪了 //hdu robot #include <cstdio> #include <iostream> #include <cmath> #include <cstring> using namespace std; inline void RD(int &ret) { char c; do { c = getchar(); } while(c < '0' || c > '9') ;…

D. Broken robot time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You received as a gift a very clever robot walking on a rectangular board. Unfortunately, you understood that it is broken a…

Robot Time Limit: 8000/4000 MS (Java/Others)    Memory Limit: 102400/102400 K (Java/Others)Total Submission(s): 158    Accepted Submission(s): 46 Problem Description Michael has a telecontrol robot. One day he put the robot on a loop with n cells. Th…

Robot Time Limit: 8000/4000 MS (Java/Others)    Memory Limit: 102400/102400 K (Java/Others)Total Submission(s): 5906    Accepted Submission(s): 1754 Problem Description Michael has a telecontrol robot. One day he put the robot on a loop with n cells.…

You received as a gift a very clever robot walking on a rectangular board. Unfortunately, you understood that it is broken and behaves rather strangely (randomly). The board consists of N rows and M columns of cells. The robot is initially at some ce…

题意:所有的格子围成一个圈,标号为1~n,若从格子1出发,每次指令告知行走的步数,但可能逆时针也可能顺时针走,概率都是1/2,那么问走了m次指令后位于格子l~r(1≤l≤r≤n)的概率. 分析: 1.因为m次指令后不知道会走到哪,会有很多种可能,但是知道从哪里出发,所以起始状态是已知的,在最初的状态,位于格子1是必然的,概率为1. 2.本题应用滚动数组,因为每次指令后都会延伸出无数种可能,这些可能是在前一种状态的基础上延伸的,而且延伸过后前一种状态的值不再有意义,完全可以被当前状态所覆盖. 3.…

这个题目看网上好多题解都是直接O(n*m)卡过.我是这么做的. 对于m次操作,统计每个w的次数.然后对每个w做矩阵乘法. 这样直接做矩阵乘法是会TLE的. 又由于这里的矩阵很特殊,一次乘法可以降维成O(n^2). -------------------------- 怎么降维的可以这样模拟下: a b c      a b c     a*a+2bc  c*c+2ab   b*b+2ac c a b  *  c a b =  b*b+2ac  a*a+2bc  c*c+2ab b c a    …