The local TV station of Marathon wants to report on the classical long distance run. There are k locations p1,…, pk. The first runner is expected to arrive at location pi at time si, and at time ti the last runner to report about will have passed. It takes ai j to move a camera team from pi to pj. The TV station wants to use as few camera teams as possible to broadcast from all k locations pi from si to time ti. Model the problem to minimize the number of camera teams as a bipartite maximum matching problem.