In this report, we study on the intermodal transportation system of Pearl River Delta city group. In the system, each city is regarded as a node. For convenience, we remove some unimportant cities and simplify the system from 14 nodes to 5 nodes. Because people need to travel from one city to another, we define a set of directed links between nodes, and each link has some specific attributes such as tail (origin), head (destination), transport mode, cost, duration, etc.
We choose C++ language to code the defined network. In this report, we want to find the cheapest path in terms of the attribute from an origin s to a destination d.
We use link label setting method to find the shortest path for an intermodal transportation routing problem. This method works for a network with parallel links. Also, in the network, link attribute must be nonnegative.