I Can't Compile C++ Program

Solution 1:

You have to rename the file from CCC.Cpp to CCC.cpp first and then compile your application by G++ (C++ compiler).

Reproducible way:

sudo apt-get install g++

mv CCC.Cpp CCC.cpp
g++ CCC.cpp -o CCC
./CCC

Also you should not use root account for daily non-administrative task.