1.前言
用JS實現一個簡單的單向鏈表，並完成相關的功能
2.功能說明
- push(value):從鏈表尾部添加一個新的節點
- insertAfer(value,item):向鏈表中的item節點之后插入一個 值為value的新節點
- remove(value):刪除鏈表中值為value的節點
- removeAt(pos):刪除鏈表中第pos個節點
- find(value):查找鏈表中值為value的節點
- findPrevious(value):查找鏈表中值為value的節點的前一個節點
- indexof(vallue):查找鏈表中值為value的節點的索引值，如果查找不到則返回-1
- size():獲取當前鏈表的長度
- getHead():獲取當前鏈表的頭節點
- print():打印當前鏈表，供測試用
3. 代碼實現
3.1 創建鏈表類
1 //創建一個Node輔助類，用來生成節點 2 function Node(value) { 3 this.value = value; 4 this.next = null; 5 } 6 7 //鏈表類 8 function LinkedList() { 9 this.head = null; 10 this.length = 0; 11 //向鏈表尾部追加元素 12 this.push = push; 13 //從鏈表中查找某個元素 14 this.find = find; 15 //在鏈表中任意一個元素之后插入一個元素 16 this.insertAfter = insertAfter; 17 //從鏈表中查找任意元素節點的前一個節點 18 this.findPrevious = findPrevious; 19 //從鏈表中刪除值為value的元素 20 this.remove = remove; 21 //返回當前鏈表的長度 22 this.size = size; 23 //查找某個元素在鏈表中的索引值 24 this.indexof = indexof; 25 //刪除鏈表中第pos個元素 26 this.removeAt = removeAt; 27 //獲取鏈表中第一個元素 28 this.getHead = getHead; 29 //打印當前的鏈表，供測試用 30 this.print = print; 31 }
2.1 push(value):從鏈表尾部添加一個新的節點
function push(value) { var node = new Node(value); if (this.head == null) { this.head = node; } else { var current = this.head; while (current.next != null) { current = current.next; } current.next = node; } length++; }
3.3 insertAfer(value,item):向鏈表中的item節點之后插入一個 值為value的新節點
function insertAfter(value, item) { var node = new Node(value); var current = this.find(item); if (current == null) { return console.log('找不到元素'); } node.next = current.next; current.next = node; length++; }
3.4 remove(value):刪除鏈表中值為value的節點
function remove(value) {
var current = this.find(value);
if (!current) {
return console.log('鏈表中找不到被刪除的元素');
}
var previous = this.findPrevious(value);
if (!previous) {
this.head = current.next;
} else {
previous.next = current.next;
}
this.length--;
}
3.5 removeAt(pos):刪除鏈表中第pos個節點
function removeAt(pos) { if (pos > -1 && pos < length) { var current = this.head; var index = 0; if (pos === 0) { this.head = current.next; } else { while (index < pos) { var previous = current; current = current.next; index++; } previous.next = current.next; } length--; } else { return null; } }
3.6 find(value):查找鏈表中值為value的節點
function find(value) { var currentNode = this.head; if (currentNode == null) { console.log("這是一個空鏈表！！！"); return null; } if (currentNode.value === value) { return currentNode; } while (currentNode.next) { currentNode = currentNode.next; if (currentNode.value === value) { return currentNode } } console.log("沒有找到該元素！！！"); return null; }
3.7 findPrevious(value):查找鏈表中值為value的節點的前一個節點
function findPrevious(value) {
var current = this.head;
if (current == null) {
console.log('這是一個空鏈表');
return null;
}
if (current.value === value) {
console.log('當前查找的節點為鏈表的頭節點，頭節點前再無節點');
return null;
}
while (current.next) {
if (current.next.value === value) {
return current;
}
current = current.next;
}
console.log('找不到該元素的前一個元素');
return null;
}
3.7 indexof(vallue):查找鏈表中值為value的節點的索引值，如果查找不到則返回-1
function indexof(value) { var current = this.head; var index = 0; if (current == null) { return null; } else { while (current) { if (current.value === value) { return index; } index++; current = current.next; } } return -1; }
3.8 size():獲取當前鏈表的長度
function size(){ return length; }
3.9 getHead():獲取當前鏈表的頭節點
function getHead(){ return this.head; }
3.10 print():打印當前鏈表，供測試用
function print() { var current = this.head; while (current != null) { console.log(current.value); current = current.next; } }
4. 功能測試
var list = new LinkedList(); for (var i = 1; i < 6; i++) { list.push(i); } list.print();
5.完整代碼
完整代碼請戳☞☞☞LinkedList.js
（完）