#include<bits/stdc++.h>

using namespace std;

const int N=52;

int n;

int a[N][N];

int main()

{

	scanf("%d",&n);

	for(int i=1;i<=n;i++)

		for(int j=1;j<=n;j++)

			scanf("%d",&a[i][j]);

	for(int i=2;i<=2*n;i++)

	{

		if(i<=n+1) for(int j=1;j<=i-1;j++) cout<<a[n-i+j+1][j]<<" ";

		else for(int j=i-n;j<=n;j++) cout<<a[n-i+j+1][j]<<" ";

	}

	puts("");

	return 0;

}