chr1stopher

Description‘Snakes and Ladders’ or ‘Shap-Ludu’ is a game commonly played in Bangladesh. The game is so common that it would be tough to find a person who hasn’t played it. But those who haven’t played it (unlucky of course!) the rules are as follows.1.Th

题目链接题目大意：有NNN个房间，其中两个房间 AAA,BBB 里各有一个人。有MMM对房间通过双向边连通。每一个时刻，每个人有一定概率pip_ipi​留在 iii 号房间，或者有1−pi1-p_i1−pi​的概率离开，等概率前往相邻房间。两人一旦处于同一房间则立即停下来。求对于所有的房间 iii，两人在 iii 号房间相遇的概率是多少PS:1.在过道内相遇不算2.所有房间保证连通解法：考虑DP，设f[i][j]f[i][j]f[i][j] 为一个人在房间 iii ，同时另一个人在 房间 jj

模板题：洛谷P3389高斯消元法Code:int n;double a[MX][MX];double ans[MX];void guess(){ for(int i = 1;i <= n;++i){ int r = i; for(int j = i + 1;j <= n;++j){ if(fabs(a[r][i]) < fabs(a[j][i])) r = j; } if(fabs(a[r][i]) < eps){ printf("No S