import java.util.ArrayList;
import java.util.Scanner;
import java.lang.Object;
public class Minimization {


	ArrayList <String> minTerms = new ArrayList();
	ArrayList<String> commonElements = new ArrayList();




	int n , index ;
	char[] variables;
	String[] compVariables;

	public void setVariables(String minTerm) {
		Scanner read = new Scanner(minTerm);
		String word = minTerm ;
		Scanner scan = new Scanner(word);
		int max = 0;
		n=0 ;
		int k = 0 ;


		while (scan.hasNext()) {
			int y = scan.nextInt();
			if (y > max)
				max = y;

		}
		n = (int) Math.ceil(Math.log(max + 1) / Math.log(2));

		while (read.hasNext()) {
			int x = read.nextInt();
			commonElements.add(String.valueOf(x));
			String number = convertBinary(x);
			minTerms.add(number);

		}

//		variables = new char[n];
//		compVariables = new String[n];
//		for (int i = 0; i < n; i++) {
//			variables[i] = (char) ('A' + i);
//			compVariables[i] = variables[i] + "'";
//		}
	}

//	public int countOccurences(String binary) {
//		return (binary.length() - binary.replace("1", "").length());
//	}

	public String convertBinary(int minterm) {
		String result = "" ;
			for (int j = n - 1; j >= 0; j--) {
				if (minterm < Math.pow(2, j))
					result += "0";
				else {
					result += "1";
					minterm = (int) (minterm - Math.pow(2, j));
				}
		}
		return result ;
	}

	public void minimization (){
		boolean flag = true ;
		int Size = minTerms.size();
		while (flag) {
			for (int i =0 ; i < Size ; i++ ) {
				flag = false ;
				for (int j =i+1 ; j < Size; j++ ) {
		            if (ComparingTerms(minTerms.get(i),minTerms.get(j))) {
		                 SetDashes(minTerms.get(i), index);
		                 String s = new String();
		                 s += commonElements.get(i);
		                 s += ",";
		                 s += commonElements.get(j);
		                 commonElements.add(s);
		                    flag = true ;
		            }
				}

			}
		}
		for(int l = 0 ; l< Size ; l++)   // print minTerms >> just for testing
			System.out.println(minTerms.get(l));
		for(int l = 0 ; l< commonElements.size() ; l++)
			System.out.println(commonElements.get(l));

	}






	public boolean ComparingTerms (String a , String b) {
		index = 0 ;
		int k = 0 ;
		int count = 0 ;
		for (int i = 0 ; i< a.length() ; i++)
		{
			if (a.charAt(i)!= b.charAt(i)){
				count++ ;
				k = i ;
			}
		}
		if (count == 1){
		    index = k ;
		    return true ;
		}
		return false ;
	}

	public void SetDashes (String a , int x) {
		String s = a ;
		 StringBuilder myBuilder = new StringBuilder(s);
		    myBuilder.setCharAt(x, '-');
		    s = myBuilder.toString();
		minTerms.add(s);


	}


	public static void main(String[] args)
	{
		String min = "1 2 4 5 6 12 13 14";
		Minimization l = new Minimization() ;
		l.setVariables(min);
		l.minimization();







			}




}