Combinatorics.java

import java.util.Arrays;

public class Combinatorics
{
    public static void main(String[] args)
    {
        final String[][] champs = new String[][] {
                { "Support#1", "Support#2", "Support#3" },
                { "Bruiser#1" },
                { "ADC#1", "ADC#2" }
        };

        final int types = champs.length;
        final int maxPerType = Arrays.stream(champs).mapToInt(e -> e.length).max().getAsInt();
        final int maxPerm = (int)Math.pow(types, maxPerType);
        final int combo[] = new int[types];

        next:
        for (int perm = 0; perm < maxPerm; perm++, combo[0]++)
        {
            final StringBuilder b = new StringBuilder("Team: ");

            for (int i = 0; i < types; i++)
            {
                // Carry over if needed.
                if (i + 1 < types && combo[i] >= maxPerType)
                {
                    combo[i + 1]++;
                    combo[i] %= maxPerType;
                }

                if (combo[i] >= champs[i].length) continue next;
                b.append(champs[i][combo[i]]).append(' ');
            }

            System.out.println(b);
        }
    }
}