#include<bits/stdc++.h>

using namespace std;
const int N=505;
int g[N][N];
int main()
{
    int n;
    cin>>n;
    for(int i=1;i<=n;++i)
        for(int j=1;j<=n;++j)
            cin>>g[i][j];

    int idx=1,length=2;
    while(length<=2*n){
        if(idx%2){
            if(length<=n+1){
            for(int i=1;i<=length-1;++i)
                cout<<g[length-i][i]<<' ';
            }
            else{
                int t=length-n-1;
                for(int i=t+1;i<=n;++i)
                    cout<<g[length-i][i]<<' ';
            }
        }
        else{
            if(length<=n+1){
            for(int i=1;i<=length-1;++i)
                cout<<g[i][length-i]<<' ';
            }
            else{
                int t=length-n-1;
                for(int i=t+1;i<=n;++i)
                    cout<<g[i][length-i]<<' ';                
            }
        }
        ++idx;
        ++length;
    }
}