#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <vector>

using namespace std;

int packages[50000];
bool assignment [50000];

int comp(const void *i1, const void *i2)
{
	int a1 = *(int*)i1;
	int a2 = *(int*)i2;

	return a1 > a2;
}

int main(void)
{
	int p;

	scanf("%d\n", &p);
	while (p)
	{
		for (int i = 0; i < p; i++)
		{
			scanf("%d", &(packages[i]));
		}
		qsort(&(packages[0]), p, sizeof(int), comp);

		for (int i = 0; i < (int)(p/2); i++)
		{
			printf("%d-A %d-B ", packages[i], packages[p-i-1]);
		}
		if (p % 2)
		{
			printf("%d-A", packages[(int)(p/2)]);
		}
		printf("\n");
		scanf("%d\n", &p);
	}

	return 0;
}