#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

bool cmp(int a, int b)
{
	return (b < a);
}

int main(void)
{
	vector<int> pack;
	int npacks;
	int tmp;
	bool nexta = false;

	while(true){
		cin >> npacks;
		if(npacks == 0)
			break;

		for(int i=0; i<npacks; i++){
			cin >> tmp;
			pack.push_back(tmp);
			//cout << tmp << endl;
		}

		sort(pack.begin(), pack.end(), cmp);

		cout << pack.back() << "-A";
		pack.pop_back();
		nexta = false;

		for(vector<int>::iterator it = pack.begin(); it != pack.end(); it++){
			cout << " " << *it;
			if(nexta){
				cout << "-A";
			}else{
				cout << "-B";
			}
			nexta = !nexta;
		}
		cout << endl;
		
		pack.clear();
	}
	return 0;
}