标签：algorithm 算法 codeforces acm
Toastman came up with a very easy task. He gives it to Appleman, but Appleman doesn‘t know how to solve it. Can you help him?
Given a n?×?n checkerboard. Each cell of the board has either character ‘x‘, or character ‘o‘. Is it true that each cell of the board has even number of adjacent cells with ‘o‘? Two cells of the board are adjacent if they share a side.
The first line contains an integer n (1?≤?n?≤?100). Then n lines follow containing the description of the checkerboard. Each of them contains n characters (either ‘x‘ or ‘o‘) without spaces.
Print "YES" or "NO" (without the quotes) depending on the answer to the problem.
3 xxo xox oxx
YES
4 xxxo xoxo oxox xxxx
NO
#include <cstdio>
#include <cmath>
#include <cstring>
#include <algorithm>
#include <string>
#include <iostream>
using namespace std;
char a[105][105];
int main()
{
int n;
char c;
int flag;
cin >> n;
memset(a, 0, sizeof(a));
for(int i=1; i<=n; i++)
for(int j=1; j<=n; j++)
{
cin >> c;
if (c == 'o')
a[i][j] = 1;
}
flag = 1;
for(int i=1; i<=n; i++)
for(int j=1; j<=n; j++)
{
int cnt = 0;
if (a[i-1][j])
++cnt;
if (a[i+1][j])
++cnt;
if (a[i][j-1])
++cnt;
if (a[i][j+1])
++cnt;
if (cnt & 1)
{
flag = false;
break;
}
}
if (flag)
cout << "YES" << endl;
else
cout << "NO" << endl;
return 0;
}Codeforces Round #263 (Div. 2) proA
标签：algorithm 算法 codeforces acm
原文地址：http://blog.csdn.net/notdeep__acm/article/details/38858277
