A teaching service wants to assign, m students, to n mentors. Let's assume that m = 2n and that each mentor is only assigned two students and each student is only assigned one mentor. Additionally, the teaching center only wants to assign students to mentors who have the same skill set (ex. math students to math mentors).

Model this as a transportation problem using paramaters; s,d,u, and c (s = supply, d = demand, c = cost) that has a feasible solution if one exists. If needed, you may define new paramaters.