#include <iostream>
#include <algorithm>
using namespace std;
int n,a[1000000],b[1000000];
int tree[1000006];
int lowbit(int x){
	return x&(-x);
}
int main() {
	freopen("sort.in","r",stdin);
	freopen("sort.out","w",stdout);
	cin>>n;
	int cnt1=0,cnt2=0;
	for(int i=1;i<=n;i++){
		if(i&1) cin>>a[++cnt1];
		else cin>>b[++cnt2];
	}
	sort(a+1,a+1+cnt1);
	sort(b+1,b+1+cnt2);
	cnt1=cnt2=0;
	for(int i=1;i<=n;i++){
		if(i&1) cout<<a[++cnt1]<<" ";
		else cout<<b[++cnt2]<<" ";
	}
	return 0;
}