我想提前说明这是一个家庭作业。我已经尝试了很多不同的方法来解决问题,但是我已经没有任何想法为什么我没有得到期望的输出。
问题
编写一个程序,以递归方式跟踪如何生成斐波那契数(对于任何N),并以以下方式显示跟踪:
示例(N=4):
问题
编写一个程序,以递归方式跟踪如何生成斐波那契数(对于任何N),并以以下方式显示跟踪:
示例(N=4):
Entering level 0
Entering level 2
Entering level 4
Exiting level 4
Entering level 3
Exiting level 3
Exiting level 2
Entering level 1
Entering level 3
Exiting level 3
Entering level 2
Entering level 4
Exiting level 4
Entering level 3
Exiting level 3
Exiting level 2
Exiting level 1
Exiting level 0
我的主要:
public class A5main {
public static void main(String[] args) {
//n holds user input
//level is the current level of the tree
//fibonacci is a5class object
int n;
int level=0;
a5class fibonacci= new a5class();
Scanner keyboard = new Scanner(System.in);
//Ask user for input
System.out.println("Enter a number up to which Fibonacci series to print: ");
n = keyboard.nextInt();
System.out.println("Fibonacci trace of: " + n);
//Pass input to fibonacci.trace method with arguments n, level.
fibonacci.trace(n,level);
}
}
我的班级:
package a5main;
public class a5class {
int fibWork;
public a5class()
{
}
public int trace(int t, int level)
{
//Accepts t and level as an argument.
//Lets uer know what level they are entering
System.out.println("Now entering level " + level);
//If t<=1 just return the value
if (t<=1)
{
System.out.println ("\tNow exiting level " + level);
return t;
}
//Else use recurssion to figure out the fibonacci sequence
//and determine what level you are on.
else
{
fibWork = trace(t-1, level+1) + trace(t-2, level+1);
System.out.println ("\tNow exiting level " + level);
return t;
}
}
}
(我在这里放了 \t,以便更容易看到它的退出位置)
我的输出:
Enter a number up to which Fibonacci series to print:
4
Fibonacci trace of: 4
Now entering level 0
Now entering level 1
Now entering level 2
Now entering level 3
Now exiting level 3
Now entering level 3
Now exiting level 3
Now exiting level 2
Now entering level 2
Now exiting level 2
Now exiting level 1
Now entering level 1
Now entering level 2
Now exiting level 2
Now entering level 2
Now exiting level 2
Now exiting level 1
Now exiting level 0
我还尝试过在创建对象时不将“level”传递到方法中,而是让它等于0,但是到目前为止没有成功。
虽然我的方法可能并不完全错误,但是我注意到它在退出第3级别后,并在下一个序列中重新进入该级别,这似乎也不正确。
我非常感谢任何帮助或指导。即使只是给出正确方向的指针也会受到赞赏。我认真对待编程,并希望真正理解它。 我不想“假装”通过,并获得毫无价值的学位。
谢谢!
fibWork
而不是t
(总和)。 - Gyro Gearless