4elist0510.cpp

《21天学通C＋＋》附盘的原代码。书上的每个例子在这里都有相应的C语言程序。

// Fibonacci series using recursion
#include <iostream>

int fib (int n);

int main()
{

	int n, answer;
	std::cout << "Enter number to find: ";
	std::cin >> n;

	std::cout << "\n\n";

	answer = fib(n);

	std::cout << answer << " is the " << n;
		std::cout << "th Fibonacci number\n";
	return 0;
}

int fib (int n)
{
	std::cout << "Processing fib(" << n << ")... ";

	if (n < 3 )
	{
		std::cout << "Return 1!\n";
		return (1);
	}
	else
	{
		std::cout << "Call fib(" << n-2 << ") ";
			std::cout << "and fib(" << n-1 << ").\n";
		return( fib(n-2) + fib(n-1));
	}
}