Fire Net Time Limit: 2 Seconds      Memory Limit: 65536 KB Suppose that we have a square city with straight streets. A map of a city is a square board with n rows and n columns, each representing a street or a piece of wall. A blockhouse is a small c…

题目链接:http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemCode=1002 题目大意: 给你一个n*n的地图,地图上的空白部分可以放棋子,也有墙,问最多能放多少棋子使得棋子两两不会袭击? 棋子袭击当且仅当处在同一行或者同一列上并且中间没有墙的阻隔. 真是好久没写过搜索题了..这道题都写了这么久!! 直接写dfs(x,y,now) 代表我现在站在x点,y点上,那么就只能产生两种状态,放棋子或者不放棋子. 然后写一个C(x,y)代表当…

嗯... 题目链接:https://zoj.pintia.cn/problem-sets/91827364500/problems/91827364501 这道题是想出来则是一道很简单的dfs: 将一个4*4的地图给每一个点排序,如下图: 0  1  2  3 4  5  6  7 8  9  10  11 12 13 14 15 设一个点为第k个点,那么它的坐标为(k/n,k%n),根据这个进行dfs,当k == n * n是退出dfs.如果k < n *n,就继续dfs,判断是否能放下,即要…

题目大意:有一个4*4的城市,其中一些格子有墙(X表示墙),在剩余的区域放置碉堡.子弹不能穿透墙壁.问最多可以放置几个碉堡,保证它们不会相互误伤. 解法:从左上的顶点开始遍历,如果这个点不是墙,做深度优先搜索,算出这种情况下的最多碉堡数.每做一次DFS,更新一次最大值. 参考代码: #include<iostream> #include<cstdio> #include<string.h> using namespace std; char city[6][6]; in…

题目链接 题目大意: 假设我们有一个正方形的城市,并且街道是直的.城市的地图是n行n列,每一个单元代表一个街道或者一块墙. 碉堡是一个小城堡,有四个开放的射击口.四个方向是面向北.东.南和西.在每一个口子上有一架机关枪. 假设子弹能够穿过任何距离,并且摧毁路上的碉堡.另一方面,子弹不能穿越墙. 我们的目标是在城市里设置足够多的碉堡,并且任何两个碉堡都不会互相摧毁.正确的配置是没有两个碉堡在相同的水平行或者垂直列上,除非碉堡之间有墙把它们分开.在这个问题中,我们将使用小的方形城市(最多4*4),它…

题目传送门 /* 题意:在一个矩阵里放炮台,满足行列最多只有一个炮台,除非有墙(X)相隔,问最多能放多少个炮台 搜索(DFS):数据小,4 * 4可以用DFS,从(0,0)开始出发,往(n-1,n-1)左下角走,x = cnt / n; y = cnt % n; 更新坐标, 直到所有点走完为止,因为从左边走到右边,只要判断当前点左上方是否满足条件就可以了 注意:当前点不能放炮台的情况也要考虑 g[x][y] == 'o'; 的错误半天才检查出来:) */ #include <cstdio> #…

ZOJ Problem Set - 1002 Fire Net Time Limit: 2 Seconds      Memory Limit: 65536 KB Suppose that we have a square city with straight streets. A map of a city is a square board with n rows and n columns, each representing a street or a piece of wall. A…

Fire Net Time Limit: 2 Seconds      Memory Limit: 65536 KB Suppose that we have a square city with straight streets. A map of a city is a square board with n rows and n columns, each representing a street or a piece of wall. A blockhouse is a small c…

Suppose that we have a square city with straight streets.  A map of a city is a square board with n rows and n columns, each representing a street or a piece of wall. A blockhouse is a small castle that has four openings through which  to shoot.  The…

Suppose that we have a square city with straight streets. A map of a city is a square board with n rows and n columns, each representing a street or a piece of wall. A blockhouse is a small castle that has four openings through which to shoot. The fo…