C++ :

#include<bits/stdc++.h>
using namespace std;
string x,a[100];
int n,t;
int main()
{
//	freopen("1.in","r",stdin);
//	freopen("1.out","w",stdout);	
	cin>>n;
	for(int i=0;i<n;i++)
	{
		cin>>x;
		if(x.size()%3==0) cout<<x<<" ",a[t++]=x;
	}
	cout<<endl;
	sort(a,a+t);
	for(int i=0;i<t;i++)
		cout<<a[i]<<" ";
	return 0;
}