Need a php script

**I need a php and mysql script. Is about a database with 20 towns and distance from one to another if exists route between them and a php script so i can select a departure town and a destination town and the script will calculate the number of km from one to another and will show all the towns between them on that route. An example: Are 3 towns in database A, B, C and D. I select to go from A to D. The script will calculate the number of kilometres from A to D and also will show the towns on that route, for example town B is on that route. from A to D xxxx km town B** ## Deliverables **NO DESIGN REQUIRED.**