ИСТИНА

In this problem, we need to 1) chose a profitable set of requests for goods delivery between stations in Russian railroad network, and 2) perform these requests by appropriately routing the set of available railcars. We formulate the problem as a multi-commodity flow problem in a space-time graph, and apply to it the column generation for extended formulations approach, in which columns-routes are disaggregated into arc variables when added to the restricted master problem. Real-life instances with up to 10 millions of arc variables were solved within minutes of computational time.