Heres a question about Maxime flow

. A police department in a small city consists of m precincts and operates with n shifts in each precinct. Each precinct is assigned a number of patrol cars. The j-th shift in the i-th precinct needs at least dij but at most cij patrol cars. Administrative constraints require that (1) the i-th precinct is allocated at least p cars; and (2) the j-th shift has at least cars qj cars available The police department wants to determine an allocation of patrol units that will meet al the requirements with the fewest possible patrol cars committed to the field. Formulate this problem as a minimum flow