JavaScript 实现静态链表：从 Node 类到增删操作详解

class Node {
    constructor(value) {
        this.data = value;
        this.next = null;
    }
}

class StaticLinkedList {
    constructor() {
        this.head = null;
        this.length = 0;
    }
    append(value) {
        const newNode = new Node(value);
        this.length++;
        if (this.head === null) {
            this.head = newNode;
            return;
        }
        let current = this.head;
        while (current.next != null) {
            current = current.next;
        }
        current.next = newNode;
    }
    display() {
        console.log('the static linked list is:\r\n');
        let current = this.head;
        if (current === null) {
            console.log('empty!');
            return;
        }
        while (current !== null) {
            console.log(JSON.stringify(current));
            console.log(`its value is ${current.data}\r\n`);
            current = current.next;
        }
    }
}

const staticLinkedList = new StaticLinkedList();
staticLinkedList.append(3);
staticLinkedList.append(7);
staticLinkedList.append(16);
staticLinkedList.append(24);

    /**
     * Method to insert an new element at the specific location
     *
     * @param {*} elementValue the value of the element that to be inserted
     * @param {*} index the position of the element, from 1 to maximum of the list
     * @returns true/false
     */
    insertAt(elementValue, index) {
        if (index < 1 || index > this.length + 1) {
            console.log('index is out of the range!');
            return false;
        }
        const newNode = new Node(elementValue);
        let startPos = 1;
        let current = this.head;
        while (startPos < index - 1) {
            current = current.next;
            startPos++;
        }
        newNode.next = current.next;
        current.next = newNode;
        this.length++;
        return true;
    }

removeAt(index) {
        if (index < 1 || index > this.length + 1) {
            console.log('index is out of the range!');
            return;
        }
        let current = this.head;
        let startPos = 1;
        let previous = null;
        while (startPos < index) {
            previous = current;
            current = current.next;
            startPos++;
        }
        previous.next = current.next;
        this.length--;
    }