Your first problem is to assign the trains to the $2$ fixed depots $($X and Y$)$ by

minimizing the distance traveled by trains $($only include distances from start

and end nodes of the paths to depots$).$ The distances between each node $($A$-$H$)$

can be seen from $$distances$.$txt$$ file in unit of hours. The distances between

the depot nodes and other nodes can be seen from $$depot node distances.txt$$

file $($unit hour$).$ Each depot should have at least $5$ trains assigned to it$.$ At the

start of each day a route from depot to a station cannot be used by more than

$3$ trains $($For each depot, starting node cannot be same for more than $3$ trains$).$

Provide a clear explanation of your decision variables, parameters and model

in your report. Give the assignments of nodes to depots and comment on the

results you$$ve found. Do not forget to consider the distances and paths between regular nodes $($for example path between A and H$)$Figure $1$: Depots to Nodes Representation