作业我被要求为自定义链表编写一个包含方法。 我知道递归方法应该有一个基本情况,然后是递归情况。但是,我在理解如何编写方法的递归情况时遇到了一些麻烦。到目前为止,这是我写的,但我的代码不止一次地执行基本情况。你能给我一些指导吗?在java中使用递归方法
public class OrderedList {
private Node first;
//Constructor
public OrderedList() {
this.first = null;
}
//Return the number of items in the list
public int size() {
int counter = 0;
Node pointer = this.first;
while (pointer != null) {
counter++;
pointer = pointer.next;
}
return counter;
}
//Return an array of copies of the stored elements
public Comparable[] getStore() {
Comparable[] elements = new Comparable[size()];
Node pointer = this.first;
if (this.first == null) {
return elements;
} else {
int i = 0;
while (pointer != null) {
elements[i] = pointer.data;
pointer = pointer.next;
i++;
}
return elements;
}
}
//true iff item matches a stored element
//Recursive
public boolean contains(Comparable item) {
//Base case
if (this.first == null) {
return false;
}
Node pointer = this.first;
this.first = this.first.next;
if (pointer.data.compareTo(item) == 0) {
return true;
}
//Recursive case
else {
boolean info = contains(item);
pointer.next = this.first;
this.first = pointer;
return info;
}
}
你为什么要改变该方法中的类变量?你应该使用传入的'Node',而不是'this.first'。每次调用该方法时都会更改列表的顶部。你正在销毁你的名单! – thatidiotguy