Is there a linked list in javascript?

There is no linked list in JavaScript; a linked list refers to a list composed of multiple elements. The elements are not stored continuously but are connected together with next pointers. Therefore, when adding or deleting non-head and tail elements in the linked list, you do not need to move the elements, you only need to change the next Just point to it. In JavaScript, you can use Object to simulate a linked list.

The operating environment of this tutorial: Windows 10 system, JavaScript version 1.8.5, Dell G3 computer.

Is there a linked list in javascript?

There is no linked list in javascript

What is a linked list?

The linked list is a list composed of multiple elements

The elements are not stored continuously and are connected together with the next pointer

JS There is no linked list in , but you can use Object to simulate a linked list

Common operations

Add node append

Delete node remove

Insert Node insert

Get the index indexOf

Convert the linked list to a string toString

Get the length of the linked list size

Judge whether the linked list is empty isEmpty

Array VS linked list

Array: When adding or deleting non-head and tail elements, you often need to move elements

Linked list: Adding or deleting non-head and tail elements, you are not allowed to move the elements, you only need to change the pointer of next That’s it.

The example is as follows:

JavaScript does not have a direct linked list implementation. The following is my own simple implementation of the linked list

function LinkedList(){
    var Node = function(element){
        this.element = element;
        this.next = null;
    }
    var head = null;
    var length = 0;
    // 定义append方法
    this.append = function(element){
        var node = new Node(element),
        current;
        // 当head为空时，就将新增的node作为head
        if(head === null){
            head = node
        }else{
            // 当head不为空时，将head赋值为当前值，通过判断当前值的next值是否存在遍历整个链表
            current = head;
            while(current.next){
                current = current.next;
            }
            // 遍历到链表的最后一项时，设置最后一项的next为新增的内容
            current.next = node
        }
        // 每新增一项，length都加1操作
        length++;
    }
    // 定义toString方法
    this.toString = function(){
        var string = '',
        current = head;
        // 最初将当前值定位到头部，当current存在时，将current的值添加到需要返回的string中，之后将current取为链表下一个值
        while(current){
            string += current.element + ( current.next ? ',' : '');
            current = current.next
        }
        // 遍历完整个链表之后返回string
        return string;
    }
    this.removeAt = function(position){
        // 当指定的位置没有在链表的长度范围内时直接返回null
        if(position > -1 && position < length){
            var current = head,
            index = 0,
            previous;
            // 指定为值是第一个时就将head移到下一个位置
            if(position === 0){
                head = current.next
            }else{
                // 通过遍历的方式将current移动到指定位置，使用index记录移动的距离
                while(index < position){
                    previous = current;
                    current = current.next;
                    index++;
                }
                // 删除是通过将指定位置的上一个节点的next指向指定位置的下一个节点
                previous.next = current.next
            }
            // 一旦删除成功需要将长度减一并返回删除的值
            length--;
            return current.element;
        }
        return null;
    }
    // 实现插入功能
    this.insert = function(position,element){
        // 插入的位置不在链表范围内时返回false
        if(position > -1 && position <= length){
            var current = head,
            index = 0,
            node = new Node(element),
            previous;
            // 插入内容在头部时将插入的node的next指定为current,current此时为head,然后将head指定为插入的node
            if(position === 0){
                node.next = current;
                head = node;
            }else{
                // 通过遍历的方式将指针指定到插入的位置,index记录当前移动的位置
                while(index < position){
                    previous = current;
                    current = current.next
                    index++
                }
                // 插入元素通过将插入位置的上一个元素的next指向插入的节点,并将插入的节点的next指向当前节点
                previous.next = node;
                node.next = current;
            }
            // 插入成功之后length加1
            length++;
            return true;
        }
        return false
    }
    // 实现查找指定element的index的功能
    this.indexOf = function(element){
        var index = 0,
        current = head;
        // 通过遍历的方式寻找指定元素所在的位置.
        // 当前节点存在时,判断当前节点的element是否为需要寻找的element,如果是就返回此时的index,如果不是就继续向下遍历节点
        // 当存在两个相同内容时只会返回第一个index
        while(current){
            if(current.element === element){
                return index;
            }
            current = current.next;
            index++;
        }
        return -1;
    }
}

After implementation, proceed as follows Call:

var linkedList = new LinkedList();
linkedList.append(15);
linkedList.append(10);
linkedList.insert(1,2) // true
linkedList.insert(2,2) // true
linkedList.toString() // "15,2,2,10"
linkedList.removeAt(3) // 10
linkedList.toString() // "15,2,2"
linkedList.indexOf(2) // 1

[Related recommendations: javascript video tutorial, web front-end]

The above is the detailed content of Is there a linked list in javascript?. For more information, please follow other related articles on the PHP Chinese website!