I'm not sure what everyone means when they say that the arduino program uses c/c++ when the commands are completely different.
The commands are not completely different to standard C/C++ but there are Arduino explicit extensions to control the Arduino hardware.
Almost without exception the whole of the C/C++ language is available on the Arduino but any program will need to interact with the user an/or external hardware hence the Arduino extensions. The Arduino reference page details these extensions as well as some standard C/C++ functions but the list is not exhaustive, nor could it be.
One thing that the Arduino IDE does is to hide some the the mechanics of C/C++ by not requiring there to be a main() function written by the user. Rather it is added during the compilation process but as I said in my previous reply you can write your own but you will then also be responsible for initialising the Arduino hardware environment which the Arduino compilation process also does behind the scenes.