#include <bits/stdc++.h>
#define N 1000005
using namespace std;
int n, a[N], b[N];
int main() {
    ios::sync_with_stdio(false);
    cin.tie(0),cout.tie(0);
    freopen("sort.in", "r", stdin);
    freopen("sort.out", "w", stdout);
    cin >> n;
    for (int i = 1; i <= n; i++) {
        cin >> (i % 2 ? a[i] : b[i]);
    }
    sort(a + 1, a + n + 1);
    sort(b + 1, b + n + 1);
    int inda = 1, indb = 1;
    while(a[inda] == 0) inda++;
    while(b[indb] == 0) indb++;
    for (int i = 1; i <= n; i++) {
        if (i % 2) {
            cout << a[inda++] << " ";
        } else {
            cout << b[indb++] << " ";
        }
    }
    return 0;
}