List<Score> matchCoupleFirst(Map<Person, List<Score>> table){
        System.out.print("matching first");
        List<Score> ret = new ArrayList<>();
        new ArrayList<>(table.keySet()).forEach(self -> {
            Stream.of(table.get(self))
              .filter(sls -> sls != null && !sls.isEmpty())
              .map(sls -> table.get(sls.get(0).target))
              .filter(tls -> tls != null && !tls.isEmpty())
              .map(tls -> tls.get(0))
              .filter(sc -> sc.target.equals(self))
              .peek(sc -> removeFromTable(table, sc.self))
              .peek(sc -> removeFromTable(table, sc.target))
              .forEach(ret::add);
        });
        System.out.println(ret);
        return ret;
    }