This project based on the below question, Turkey cities used.

https://stackoverflow.com/questions/222413/find-the-shortest-path-in-a-graph-which-visits-certain-nodes

[start -> must visit -> return to start]

put all cities to graph

then calculate dijkstra

then filter which includes given cities

then return whichever one of them has the smallest value

1. find all combinations of certain cities

2. find the shortest path with Dijkstra between pair nodes

3. find all permutations of route

4. calculate each possible solution distance

5. make calculated distances ordered