C++ separation compile multiple files into object files via g++ -c

1.The project structure as below

The Model folder and main cpp file.

2.Compile the files in Model folder via g++ -c as below and generate *.o  object files.We can see object files end with o  as below screenshot

g++ -c -std=c++2a -I. ./Model/*.h ./Model/*.cpp -luuid -lpthread

3.Then compile the object files and generate  executable files. Then we can run the ultimate executable file h1 via run ./h1 command 

g++ -g -std=c++2a -I. *.o main.cpp -o h1 -luuid -lpthread

From another perspective,we can compile multiple files via seperation compilatiojn  into executable file once. As below

g++ -c -std=c++2a -I. ./Model/*.h ./Model/*.cpp -luuid -lpthread;g++ -g -std=c++2a -I. *.o main.cpp -o h1 -luuid -lpthread;

 Run the executable file h1