#include<fstream>
using namespace std;
ifstream fin("pion.in");
ofstream fout("pion.out");
int n,i,j, a[50][50], c[50][50];
void citire()
{ int i,j;
  fin>>n;
  for(i=1;i<=n;i++)
	for(j=1;j<=n;j++) fin>>a[i][j];
}
void pd()
{ int i,j;
  for(i=2;i<=n;i++)
	  for(j=1;j<=n;j++)
		 if(a[i][j]==0)
            c[i][j]=c[i-1][j];
		  else if(c[i-1][j-1]>c[i-1][j+1])
                c[i][j]=c[i-1][j-1]+1;
            else c[i][j]=c[i-1][j+1]+1;

}
void drum(int i, int j)
{
   if(i==1) fout<<i<<" "<<j<<endl;
   else { if(a[i][j]==0) drum(i-1,j);
		  else if(c[i-1][j-1]+1==c[i][j])
					 drum(i-1,j-1);
			   else drum(i-1,j+1);
		  fout<<i<<" "<<j<<endl;
        }
}
void afis()
{
  int max=0,jm;
  for(j=1;j<=n;j++) if(c[n][j]>max) { max=c[n][j]; jm=j; }
  fout<<max<<endl;
  drum(n,jm);
}

int  main()
{ citire();
  pd();
  afis();
  fin.close();
  fout.close();
  return 0;
}