#include <bits/stdc++.h>
using namespace std;
long long a[101];
int main() {
  int n;
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> a[i];
  }
  sort(a, a + n);
  for (int i = 0; i < n; i += 2) {
    cout << a[i] << " ";
  }
  for (int i = n - 1 - n % 2; i >= 1; i -= 2) {
    cout << a[i] << " ";
  }
  return 0;
}
