Sorting can be applied to different groups of people and in different locations. For example:
Army. You have to sort appropriate (strong, healthy) ppl to the army and send inappropriate to somewhere else.
Sexual orientation. Short guys to the gay club and straights to a normal club. (can be women too)
Toilet. Men in the male cabin, woman to the lady's cabin.
etc.

On the road in front of the player stands a queue of two groups of characters: A and B. Characters coming up to the player by turn and waiting while he identifies them and chooses the place that suits best.