#include <bits/stdc++.h>
using namespace std;
//
#define ll long long
#define ull unsigned long long
#define mx 100010
#define mod 1000000007
#define inf INT_MAX
#define pi acos(-1.0)
#define endl '\n'
#define pb push_back
#define pll pair<ll, ll>
#define vll vector<ll>
#define vpll vector<pll>
#define fastio ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0)
//
int main() {
    ll n;
    cin >> n;
    ll ar[n];
    for (ll i = 0; i < n; i++) cin >> ar[i];
    sort(ar, ar + n);
    stack<ll> st, st1;
    ll sum = 0, sum1 = 0, cnt = 0, cnt1 = 0;
    for (ll i = n - 1; i >= 0; i--) {
        if (cnt < n / 2 && cnt1 < n / 2) {
            if (sum <= sum1) {
                st.push(ar[i]);
                cnt++;
                sum += ar[i];
            }
            else {
                st1.push(ar[i]);
                cnt1++;
                sum1 += ar[i];
            }
        }
        else if (cnt == n / 2) st1.push(ar[i]);
        else st.push(ar[i]);
    }
    while (!st.empty()) {
        cout << st.top() << " ";
        st.pop();
    }
    cout << endl;
    while (!st1.empty()) {
        cout << st1.top() << " ";
        st1.pop();
    }
}