This problem is an example of the Travelling Postman Problem. It is similar to the Travelling Salesman Problem (TSP), but the key difference is that in the Travelling Postman Problem, the postman must cover each edge (path between two points) at least once while minimizing the total distance traveled. The TSP is concerned with visiting each node once and returning to the origin, while the Travelling Postman Problem focuses on the minimum distance to cover the required paths.
In this case, the postman is asked to visit all post offices, starting and ending at the same location, and without visiting any post office twice. This aligns with the Travelling Postman Problem.