尾部调用

public class BeanInfoDemo {
    public static void main(String[] args) {
        Fibonacci(50);
    }

    private static void Fibonacci(int n) {
        long t1 = System.currentTimeMillis();
        System.out.println("传统：" + FibonacciC(n));
        long t2 = System.currentTimeMillis();
        System.out.println("传统耗时：" + (t2 - t1));
        System.out.println("尾部：" + FibonacciNew(n, 1, 1));
        long t3 = System.currentTimeMillis();
        System.out.println("尾部耗时：" + (t3 - t2));
    }

    public static long FibonacciC(long n) {
        if (n <= 2) {
            return 1;
        }
        return FibonacciC(n - 1) + FibonacciC(n - 2);
    }

    public static long FibonacciNew(long n, long ac1, long ac2) {
        if (n <= 2) {
            return ac2;
        }
        return FibonacciNew(n - 1, ac2, ac1 + ac2);
    }

}