Okk, you can test whether it's installed:
type as a user gc<tab> , if gcc is shown it's alright.
If you do not have gcc installed:
go to the console, get root (type 'su'), type 'urpmi gcc' .
GCC is fine for C - compiling, I prefer G++ for C++ (to get G++, just type urpmi G++).
If urpmi asks whether you want to install dependencies; allow it.