POJ 1753 Flip Game BFS
来源:互联网 发布:白色休闲裤搭配知乎 编辑:程序博客网 时间:2024/05/17 22:36
Flip Game
Time Limit: 1000MS Memory Limit: 65536KTotal Submissions: 27410 Accepted: 11902
Description
Flip game is played on a rectangular 4x4 field with two-sided pieces placed on each of its 16 squares. One side of each piece is white and the other one is black and each piece is lying either it's black or white side up. Each round you flip 3 to 5 pieces, thus changing the color of their upper side from black to white and vice versa. The pieces to be flipped are chosen every round according to the following rules:
Consider the following position as an example:
bwbw
wwww
bbwb
bwwb
Here "b" denotes pieces lying their black side up and "w" denotes pieces lying their white side up. If we choose to flip the 1st piece from the 3rd row (this choice is shown at the picture), then the field will become:
bwbw
bwww
wwwb
wwwb
The goal of the game is to flip either all pieces white side up or all pieces black side up. You are to write a program that will search for the minimum number of rounds needed to achieve this goal.
- Choose any one of the 16 pieces.
- Flip the chosen piece and also all adjacent pieces to the left, to the right, to the top, and to the bottom of the chosen piece (if there are any).
Consider the following position as an example:
bwbw
wwww
bbwb
bwwb
Here "b" denotes pieces lying their black side up and "w" denotes pieces lying their white side up. If we choose to flip the 1st piece from the 3rd row (this choice is shown at the picture), then the field will become:
bwbw
bwww
wwwb
wwwb
The goal of the game is to flip either all pieces white side up or all pieces black side up. You are to write a program that will search for the minimum number of rounds needed to achieve this goal.
Input
The input consists of 4 lines with 4 characters "w" or "b" each that denote game field position.
Output
Write to the output file a single integer number - the minimum number of rounds needed to achieve the goal of the game from the given position. If the goal is initially achieved, then write 0. If it's impossible to achieve the goal, then write the word "Impossible" (without quotes).
Sample Input
bwwbbbwbbwwbbwww
Sample Output
4
Source
Northeastern Europe 2000
POJ训练计划枚举第一题。。。话说这第一眼为什么能看的出是枚举 %>_<%
一看是DFS模板题,而且每个棋子最多翻一回(翻两回等于没翻)。确实可以枚举所有情况的说。。。不是也有人写DFS么。。。
我果断队列开小WA了一次。
还有些高大上的位运算神马的。反正我2965还在WA,如果重写就试试位运算写法。
某人提供的“官方数据”(显然不科学啊啊啊,按照上面的数据,10^6的队列不可能不够用啊)
官方测试数据: 这些都过了,就不可能WA了。bwbwwwwwbbwbbwwbImpossiblebwwbbbwbbwwbbwww4wwwwwwwwwwwwwwww0bbbbbbbbbbbbbbbb0bbbbbwbbbbbbbbbbImpossiblebwbbbwbbbwbbbbbbImpossiblebwbbwwwbbwbbbbbb1wwwwwwwbwwbbwwwb1wwwwwwwwwwwbwwbb1wbwbbwbwwbwbbwbwImpossiblebbbbbwwbbwwbbbbb4bwwbwbbwwbbwbwwb4bbwwbbwwwwbbwwbbImpossiblebbwbbbbwwwbbwwwbImpossiblewwwbwwbwwbwwwwbwImpossiblebbbbwwwwwwbbwbbbImpossiblebwwbwbwbwbbbwbbb4bwbbbwbbbwbwbbbw5wbwbbbbbbbwwwbbb6bbwbbbbbwbwbbbbb5
代码:
#include <iostream>using namespace std;struct map{bool m[6][6][2];int x,step;}queue[800010],tem;int main(){string s; int i,j,k,l;tem.x=tem.step=0;for (i=1;i<=4;++i){cin>>s;for (j=0;j<4;++j)if (s[j]=='b'){tem.x++;tem.m[i][j+1][1]=1;tem.m[i][j+1][0]=1;}else{tem.m[i][j+1][1]=0;tem.m[i][j+1][0]=1;} }if (tem.x==16 || tem.x==0){cout<<'0'<<endl;return 0;}int so=0,fa=0;queue[0]=tem;while (fa<=so && so<=800001){for (i=1;i<=4;++i)for (j=1;j<=4;++j){if (tem.m[i][j][0]){tem.m[i][j][0]=0;tem.m[i][j][1]^=1;tem.m[i-1][j][1]^=1;tem.m[i+1][j][1]^=1;tem.m[i][j-1][1]^=1;tem.m[i][j+1][1]^=1; tem.x=0; tem.step++;for (k=1;k<=4;++k)for (l=1;l<=4;++l)tem.x+=tem.m[k][l][1];if (tem.x==0 || tem.x==16){cout<<tem.step<<endl;return 0;}queue[++so]=tem;tem=queue[fa];}}tem=queue[++fa];}cout<<"Impossible\n";return 0;}
kdwycz的网站: http://kdwycz.com/
kdwyz的刷题空间:http://blog.csdn.net/kdwycz
0 0
- POJ 1753 Flip Game BFS
- POJ 1753 Flip Game(BFS)
- POJ 1753 Flip Game (BFS)
- POJ 1753 Flip Game BFS/DFS
- POJ 1753 Flip Game ------- BFS & 位运算
- 位运算-BFS-Flip Game-POJ 1753
- 【BFS+状态压缩】-POJ-1753-Flip Game
- POJ 1753 Flip Game(bfs)
- poj 1753 Flip Game(位运算+bfs)
- POJ 1753 Flip Game(状态压缩BFS)
- POJ 1753 Flip Game(BFS+状态压缩)
- 【BFS|位运算】POJ-1753 Flip Game
- 【POJ】1753 - Flip Game(bfs,枚举)
- poj 1753 Flip Game(枚举,bfs)(简单)
- (POJ 1753)Flip Game <状压+BFS>
- POJ:1753-Flip Game(二进制+bfs)
- [bfs] poj 1753 Flip Game# bfs + 位存储
- POJ 1753 Flip Game BFS+位压缩状态
- Logging Intercepter例子
- 软件工程视频之面向对象
- sched_yield()功能
- maven依赖
- 关键字-implicit
- POJ 1753 Flip Game BFS
- 详解@SessionAttributes
- 关于NULL在C和C++中的区别
- 动态规划6:最长递增子序列问题
- 月薪终于10K了
- 主页面与iframe的互相访问
- Logback 配置文件例子
- Binami redmine自带SVN的配置与关联
- linux怎么查看是多少位的