general question please reply thanks in advance

[harry63]

hello everyone 

i have a question about developing apex code in salesforce. i am a fresher completed my masters in management. i trained in salesforcce as admin and developer. but i am worrying about developing apex code for a real time project.could you please tell me what percent of code is written by developers as own and what percent of code will be available from the sources like forums, google, importing the existindg code...... etc.

THANKS IN ADVANCE

HARRY