#include <iostream>
using namespace std;
int main()
{
int i, j, n, m, a[100][100];
cin>>n>>m;
for(i=1; i<=n; i++)
for(j=1; j<=m; j++)
cin>>a[i][j];
for(i=1; i<=n; i++)
for(j=1; j<=m; j++)
if(i%2==0)
cout<<a[i][j]<<" ";
cout<<endl;
for(i=1; i<=n; i++)
for(j=m; j>=1; j--)
if(i%2==1)
cout<<a[i][j]<<" ";
cout<<endl;
return 0;
}