fig03_15.cpp

这是C＋＋编程经典的书上实例的源代码。 （英文名是《C＋＋ how to program》第3版）

// Fig. 3.15: fig03_15.cpp
// Recursive fibonacci function
#include <iostream>

using std::cout;
using std::cin;
using std::endl;

unsigned long fibonacci( unsigned long );

int main()
{
    unsigned long result, number;

    cout << "Enter an integer: ";
    cin >> number;
    result = fibonacci( number );
    cout << "Fibonacci(" << number << ") = " << result << endl;
    return 0;
}

// Recursive definition of function fibonacci
unsigned long fibonacci( unsigned long n )
{
   if ( n == 0 || n == 1 )  // base case
      return n;
   else                     // recursive case
      return fibonacci( n - 1 ) + fibonacci( n - 2 );
}


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