java - 删除链表中的第k个元素(Java实现)

Question

我正在尝试这个程序，但我无法实现删除。执行进入无限循环。另外，我不确定我是否正确地形成了链表。

我在以下程序中缺少什么:

public class SpecificNodeRemoval {
private static class Node {
    String item;
    Node next;
    Node prev;

    private Node(String item, Node next, Node prev) {
        this.item = item;
        this.next = next;
        this.prev = prev;
    }
}

public static void main(String[] args) {
    int k = 3;

    Node fourth = new Node("Fourth", null, null);
    Node third = new Node("Third", fourth, null);
    Node second = new Node("Second", third, null);
    Node first = new Node("First", second, null);

    second.prev = first;
    third.prev = second;
    fourth.prev = third;
    Node list = first;

    Node result = removalKthNode(list, k);

    int j = 1;
    while(result.next!=null){
        System.out.println(j+": "+result.item);
    }
}

private static Node removalKthNode(Node first, int k) {
    Node temp = first;

    for(int i=1; i < k; i++) {
        temp = temp.next;
    }

    temp.prev.next = temp.next;
    temp.next.prev = temp.prev;

    return temp;
}
}

---

非常感谢您的回答和评论。工作程序如下所示:

public class SpecificNodeRemoval {
private static class Node {
    String item;
    Node next;
    Node prev;

    private Node(String item, Node next, Node prev) {
        this.item = item;
        this.next = next;
        this.prev = prev;
    }
}

public static void main(String[] args) {
    int k = 3;

    Node fourth = new Node("Fourth", null, null);
    Node third = new Node("Third", fourth, null);
    Node second = new Node("Second", third, null);
    Node first = new Node("First", second, null);

    second.prev = first;
    third.prev = second;
    fourth.prev = third;
    Node list = first;

    Node result = removalKthNode(list, k);

    int j = 1;
    while(result != null){
        System.out.println(j+": "+result.item);
        result = result.next;
        j++;
    }
}

private static Node removalKthNode(Node first, int k) {
    Node temp = first;

    for(int i=1; i < k; i++) {
        temp = temp.next;
    }

    temp.prev.next = temp.next;
    temp.next.prev = temp.prev;

    return first;
}
}

输出是: 1:首先 2:第二 3:第四个

Answer 1

这看起来像是罪魁祸首。

while(result.next!=null){
    System.out.println(j+": "+result.item);
}

你没有在链表中前进。

我不太确定你的意图，但你可能想写如下以避免无限循环......

while(result !=null){
    System.out.println(j+": "+result.item);
    result = result.next;
    j++;
}

但是如果你想打印整个链表，你不应该用从 removalKthNode 函数返回的值初始化 result。您应该从首先开始。

希望这是有道理的。