65 lines
1.4 KiB
C++
65 lines
1.4 KiB
C++
#include<map>
|
|
#include<string>
|
|
#include<iostream>
|
|
#include<stdio.h>
|
|
using namespace std;
|
|
map<string,int>sg;
|
|
map<string,bool>is;
|
|
int n,m;
|
|
bool judge(string str,int i,int j)
|
|
{
|
|
if(str[i * m + j] == '1' || str[i * m + j + 1] == '1' || str[i * m + m + j] == '1' || str[i * m + m + j + 1] == '1')
|
|
return false;
|
|
return true;
|
|
}
|
|
void input(string &str,int i,int j)
|
|
{
|
|
str[i * m + j]=str[i * m + j + 1]=str[i * m + m + j] = str[i * m + m + j + 1] = '1';
|
|
}
|
|
int DFS(string str)
|
|
{
|
|
if(is[str])
|
|
return sg[str];
|
|
for(int i = 0;i < n - 1;i++)
|
|
{
|
|
for(int j = 0;j < m - 1;j++)
|
|
{
|
|
if(judge(str,i,j))
|
|
{
|
|
string temp = str;
|
|
input(temp,i,j);
|
|
if(DFS(temp) == 0)
|
|
{
|
|
is[str] = 1;
|
|
sg[str] = 1;
|
|
return 1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
is[str] = 1;
|
|
sg[str] = 0;
|
|
return 0;
|
|
}
|
|
int main()
|
|
{
|
|
string str;
|
|
string temp;
|
|
while(scanf("%d %d",&n,&m)!=EOF)
|
|
{
|
|
str="";
|
|
sg.clear();
|
|
is.clear();
|
|
for(int i = 0;i < n;i++)
|
|
{
|
|
cin >> temp;
|
|
str += temp;
|
|
}
|
|
if(DFS(str))
|
|
printf("Yes\n");
|
|
else
|
|
printf("No\n");
|
|
}
|
|
return 0;
|
|
}
|