1.　　输入所在城市，打印出所在城市的物流公司
2.　　在功能1的基础上输入包裹到达城市，打印出不同物流公司相应的物流价格
3.　　在功能2的基础上输入包裹重量和类型(重货or轻货)，打印出相应的运送价格
4.　　打印出上述每个功能的程序执行时间(1. enter the city and print out the logistics company in the city.

2. input the package to the city on the basis of the function 1, and print out the corresponding logistics prices of different logistics companies

Enter the package weight and type 3. in 2 on the basis of (or, light heavy) print out the corresponding delivery price

4. print out the program execution time of each of the above functions)