单链表 append insert remove get print

节点

• value
• next

class ListNode(value){
	constructor{
		this.value = value
		this.next = null
	}
}

链表

• head
• size

class Linklist(){
	constructor{
		this.head = null
		this.size = 0
	}
}

append(value)

• 新建节点
• 判断插入位置
• 接收头节点
• 循环
• 赋值
• size++

append(value){
	const newNode = new Listnode(value)

	if(this.head === null){
		this.head = newNode
	}else{
		let current = this.head
		while(current.next !== null){
			current = current.next;
		}
		current.next = newNode;
	}
	this.size++;
}

insert(index,value)

• 判断index范围
• 新建节点
• 判断插入位置
  • 接收头节点
  • 循环
  • 赋值
• size++

insert(index.value){
	if(index < 0 || index > this.size){
		throw new Error("index out of range")
	}
	const newNode = new Listnode(value);

	if(index === 0){
		newNode.next = this.head;
		this.head = newNode;
	}else{
		let current = this.head;
		let i = 0;

		while(i < index){
			previous = current;
			current = current.next;
			i++;
		}
		newNode.next = current;
		previous.next = newNode;
	}
	this.size++;
}

remove(index)

• 判断index范围
• 接收头节点
• 判断插入位置
  • 循环
  • 赋值
• size–

remove(index){
	if(index < 0 || index > this.size){
		throw new Error("index out of range")
	}
	let current = this.head;

	if(index === 0){
		this.head = current.next
	}else{
		let previous = null;
		let i = 0;
		while(i < index){
			previous = current;
			current = current.next;
			i++;
		}
		previous.next = current.next;
	}
	this.size --;
	return current.value
}

get(index)

• 判断index范围
• 接收头节点
• 循环
• 返回值

get(index){
	if(index < 0 || index > this.size){
		throw new Error("index out of range")
	}
	let current = this.head;
	let i = 0;
	while(i < index){
		current = current.next;
		i++;
	}
	return current.value
}

print()

• 接收头节点
• push
• next
• log

print(){
	let current = this.head;
	let result = [];

	while(current.next !== null){
		result.push(curremt.value);
		current = current.next;
	}
	console.log(result.join('->'));
}