My program should prints a sequence of 20 fibonacci numbers in a simple way

As u all know the f(n) of fibonacci numbers is as follows:

0 if n=0

1 if n=1

fn-1 + fn+1 if n>1

I made the code and there's no errors , but it gives me nothing !!!

Can anyone tell me what's wrong with my code ?

#include <iostream> using namespace std; int main () { cout<<" --»(( W E L C O M E ))«-- \n\n\n"<<endl; cout<<" This program shows a series of fibonacci numbers \n\n\n"<<endl; cout<<"-------------------------------"<<endl; int n=0; int fnum; int counter=-1; while (n<=20) { if (n==1){ fnum=1; counter=counter+1; } while (n>1){ fnum=(n-1)+(n+1); counter=counter+1; } } cout<<fnum<<endl; if (n==0){ fnum=0; counter=counter+1; } return 0; }