A Two-Phase Heuristic Algorithm for the Common Frequency Routing Problem with Vehicle Type Choice in the Milk Run

Algorithm 1

Randomly generate an initial solution of (), which meets the time constraint in (9). Set the current solution , ;

then, calculate (). Set it = 1 (it records the current number of iterations).

Do while  it

 If  rand <

   Generate a neighborhood solution (, ) through the first neighborhood method

   Do while the time of the new solution (, ) is not less than

   Regenerate a neighborhood solution (, ) through the first neighborhood method

   End  do

   If  

   End if

 End if

 Execute the other three neighborhood methods using a similar process.

 it = it + 1

End  do

Output the initial satisfactory solution , and define .