精选优质文档-倾情为你奉上ABSTRACT1. INTRODUCTIONTransporting people in the morning from their homes to their works and back in the afternoon has become a big problem in big cities especially in undeveloped countries. As a partial solution of this problem, the authorities in some countries had, unofficially, left the taxicab drivers to carry different passengers to different places at the Same time. For example, a taxicab with four seats may carry four different passengers without any relation betw