Modelling of an Optimal Route

This article analyzes problems of determining the shortest way and optimal route among given towns. The model of the problem is presented as non-directional graph, where nodes are towns and crossings outside towns, and edges are roads among towns and crossings. Each node has some information attached to it: name and size of the town, maintenance organizations, and mark of the crossing. All towns are connected by roads. These roads are shown as graph edges. Each edge also has information sketched in: type of road, length of road, allowable speed on the road and other useful information. Retrieval of an optimal route is executed in two stages: finding shortest way between two towns and optimizing route to visit some towns. Algorithms to both exercises’ solutions are presented. Floyd-Warshall algorithm is selected for finding shortest way from one graph node to another selected node. Nearest neighbour algorithm is selected for route optimization. Graphical system for selected towns on Lithuanian map finds an optimal route. A solution is presented in graphical form and a list of route’s towns is written with length and time of the route. The program is written in Visual Basic language. It consists of main program’s dialog window and three class modules: points, roads and routes, which have some properties and methods. The program controls database with two tables: points and roads. Obtained results are discussed and conclusions are made