static public int fight(Group g1, Group g2) {
		while (true) {
			Iterator<Combatant> i1 = g1.getCombatants();
			while (i1.hasNext()) {
				Combatant c = i1.next();
				c.attack(g2.getMember());
			}
			Iterator<Combatant> i2 = g2.getCombatants();
			while (i2.hasNext()) {
				Combatant c = i2.next();
				c.attack(g1.getMember());
			}
			g1.removeDead();
			g2.removeDead();
			if (g1.isDefeated() || g2.isDefeated()) {
				return (g1.isDefeated()?1:0) - (g2.isDefeated()?1:0);
			}
		}
	}