《ACM程序设计》书中题目 W - 23 美丽草坪

Description

Tom's Meadow 

Tom has a meadow in his garden. He divides it into N * M squares. Initially all the squares were covered with grass. He mowed down the grass on some of the squares and thinks the meadow is beautiful if and only if

1. Not all squares are covered with grass.
2. No two mowed squares are adjacent.

Two squares are adjacent if they share an edge. Here comes the problem: Is Tom's meadow beautiful now?

Input

The input contains multiple test cases!

Each test case starts with a line containing two integers N, M (1 <= N, M <= 10) separated by a space. There follows the description of Tom's Meadow. There're N lines each consisting of M integers separated by a space. 0(zero) means the corresponding position of the meadow is mowed and 1(one) means the square is covered by grass.

A line with N = 0 and M = 0 signals the end of the input, which should not be processed

Output

One line for each test case.

Output "Yes" (without quotations) if the meadow is beautiful, otherwise "No"(without quotations).

Sample Input

2 2
1 0
0 1
2 2
1 1
0 0
2 3
1 1 1
1 1 1
0 0

Sample Output

Yes
No
No

    

     这道题的基本题意为有一个n*m铺满草的草坪，现在要求你去剪草坪，问草坪是否美丽。

草坪美丽的条件：

1.至少有一块草坪被割草了。

2.割草的草坪不能相邻。

源代码如下：

#include<bits/stdc++.h>
using namespace std;
int main()
{  int n,m,i,j,k;
   while(cin>>n>>m&&n!=0&&m!=0)
{ 
 int a[12][12];
 for(i=0;i<12;++i)
  for(j=0;j<12;++j)
   a[i][j]=1;
 for(i=1;i<=n;++i)
  for(j=1;j<=m;++j)
   { cin>>a[i][j];
     if(a[i][j]==0)k=1;
} 
 for(i=1;k==1&&i<=n;++i)
  for(j=1;j<=m;++j)
  { if(a[i][j]==0&&(a[i-1][j]==0||a[i][j-1]==0||a[i][j+1]==0||a[i+1][j]==0))
       { k=0;
         break;
   }
      
  }
  if(k)cout<<"Yes"<<endl;
  else cout<<"No"<<endl;
}
}