how about this

来源: 于 2010-01-07 16:53:49 [旧帖] [给我悄悄话] 本文已被阅读：次

If any guy sees only one pair, he walks to the side. Once one guy walks to the side, nobody else walks.

The rest look at each other. Whoever still only sees one pair, has the same count as the guy who walks aside.