Research Article

Multi-Depot Pickup and Delivery Problem with Resource Sharing

Algorithm 2

Procedure of CW algorithm.
Input: The datasets of customer and facility information including location, time window, demand, and other relevant parameters
Output: The initial feasible solution
(1)Step 1: Mark the initial distance saving values with numbers 1, 2, 3, …, (n-1)
(2)Step 2: Assign vehicles to each customer
(3)Step 3: Calculate the distance savings of new vehicle routes, which are formed by any two routes
(4)Step 4: Sort the distance savings in descending order
(5)Step 5: If new vehicle routes meet the time window and capacity constraints, then go directly to Step 6; otherwise set n=n+1 and return to Step 5
(6)Step 6: Generate a new vehicle route with two vehicle routes whose distance savings are maximum
(7)Step 7: Update the distance savings value through the fusion of vehicle routes
(8)Step 8: Generate new vehicle route with two vehicle routes whose distance savings are maximum
(9)Step 9: n = 1
(10)Step 10: If new vehicle routes meet the time window and capacity constraints, then go directly to Step 11; otherwise, return to Step 7
(11)Step 11: n = n+1
(12)Step 12: Generate new vehicle route with two vehicle routes whose distance savings are maximum
(13)Step 13: If there exists a route that serves only one, then go back to Step 7; otherwise enter Step 14
(14)Step 14: Output the service route of each vehicle