I. Introduction
In recent years, the vigorous development of ecommerce industry has promoted the development of logistics industry. In 2019,Chinese total social logistics cost accounts for 14.7% of gross domestic product while the proportion remains at 8% to 9% in developed countries. Vehicle routing problem (VRP) aims to reduce the cost of logistics and improve the satisfactions of customers. The aim of the former goal is to reduce the number of used vehicles, select the appropriate type of vehicles, reduce the energy consumption and the driving distance. The aim of the later goal is that the vehicle serves the customer within the customer's time window.