// fig05_16.cpp
// Recursive function fibonacci.
#include <iostream>
using namespace std;

long fibonacci(long number); // function prototype

int main() {
   // calculate the fibonacci values of 0 through 10
   for (int counter{0}; counter <= 10; ++counter)
      cout << "fibonacci(" << counter << ") = "
         << fibonacci(counter) << '\n';

   // display higher fibonacci values
   cout << "\nfibonacci(20) = " << fibonacci(20);
   cout << "\nfibonacci(30) = " << fibonacci(30);
   cout << "\nfibonacci(35) = " << fibonacci(35) << '\n';
}

// recursive function fibonacci                            
long fibonacci(long number) {
   if ((0 == number) || (1 == number)) { // base cases     
      return number;
   }
   else { // recursion step                                
      return fibonacci(number - 1) + fibonacci(number - 2);
   }
}


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