Nightmare Ⅱ Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 886    Accepted Submission(s): 185 Problem Description Last night, little erriyue had a horrible nightmare. He dreamed that he and hi…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=3085 Nightmare Ⅱ Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 2790    Accepted Submission(s): 781 Problem Description Last night, little erriyu…

题意:很好理解,然后注意几点,男的可以一秒走三步,也就是三步以内的都可以,鬼可以穿墙,但是人不可以,鬼是一次走两步 分析:我刚开始男女,鬼BFS三遍,然后最后处理答案,严重超时,然后上网看题解,发现是双向BFS 就一秒一秒走就行,男的一秒走3,女的一秒走1,然后走过的分别赋值男女标记,当走到对方的标记时就是答案了 然后有一个不能走的地方和两个鬼的位置曼哈顿距离搞一下就行, 注:然后涨了姿势,是队列可以直接赋值,q1=q2,以前都不知道 #include<cstdio> #include<…

联赛前该练什么?DP,树型,状压当然是爆搜啦 双向BFS就是两个普通BFS通过一拼接函数联系,多多判断啦 #include <iostream> #include <cstdio> #include <cstring> #include <algorithm> #include <cmath> #define R(a,b,c) for(register int a = (b); a <= (c); ++a) #define nR(a,b,c…

Problem Description Last night, little erriyue had a horrible nightmare. He dreamed that he and his girl friend were trapped in a big maze separately. More terribly, there are two ghosts in the maze. They will kill the people. Now little erriyue want…

http://acm.hdu.edu.cn/showproblem.php?pid=3085 出的很好的双向bfs,卡时间,普通的bfs会超时 题意方面: 1. 可停留 2. ghost无视墙壁 3. 需要检查两次某个地点是否有ghost,正要到达的时候(t),以及即将启程的时候(t+1). 在编程时需要注意的是: 当两个人汇合时,不需要检查即将启程的那次. M可以走3步,在这3步中间只需要检查是否能到达(t) 出问题在: 1. 检查时间处理的不清晰 2.普通bfs会超时 3.双向bfs需要完全…

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=3085 题目大意:给你一张n*m地图上,上面有有 ‘. ’:路 ‘X':墙 ’Z':鬼,每秒移动2步,可以穿墙,开始有两个,每开始时鬼先动. ‘M’:男生,每秒可走3步. ‘G’:女生,每秒可走1步. 解题思路:第一次写双向BFS,写了我好久,开始还是想着先bfs计算step[x][y][t]把每个位置被鬼占据的时间处理一下然后再用双向BFS计算两人相遇时间.后来发现因为鬼可以穿墙,可以直接用曼哈顿距…

Nightmare Ⅱ Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 3012    Accepted Submission(s): 856 Problem Description Last night, little erriyue had a horrible nightmare. He dreamed that he and h…

Nightmare Ⅱ Time Limit: 2000/1000 MS (Java/Others)     Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 886     Accepted Submission(s): 185 Problem Description Last night, little erriyue had a horrible nightmare. He dreamed that he and…

题目链接 单向bfs就是水题 #include <iostream> #include <cstring> #include <cstdio> #include <algorithm> #include <queue> using namespace std; const int INF = 0x3f3f3f3f; + ; struct Node { int x, y; }; int g[Max][Max]; int vis[Max][Max];…