栈
栈是一种遵从后的进先出原则的有序集合
- push(val) 添加一个新元素到栈顶
- pop() 移除栈的元素，同时返回被移除的元素
- peek() 返回栈顶的元素，不对栈做任何修改
- isEmpty() 如果栈里没有任何元素就返回true，否则返回false
- clear() 移除栈里的所有元素
- size() 返回栈里的元素个数
目录
inex.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<script src='./stack.js'></script>
<script src='./stack-es6.js'></script>
</head>
<body>
aa
</body>
</html>
stack.js
var Stack = function(){
var items = [];
// this.items = [];
this.push= function(val){
items.push(val)
}
this.pop = function(){
return items.pop()
}
this.peek = function(){
return items[items.length-1]
}
this.isEmpty = function(){
return items.length === 0
}
this.clear = function(){
items = []
}
this.size= function(){
return items.length
}
}
var s1 = new Stack()
var items = []和this.items = []的区别: this.items是公有的,s1,s2都能访问得到
var s1 = new Stack()
var s2 = new Stack()
stack-es6.js
class StackEs6{
constructor(){
this.items = []
}
push(val){
this.items.push(val)
}
pop(){
return this.items.pop()
}
size(){
return this.items.length
}
peek(){
return this.items[this.items.length-1]
}
isEmpty(){
return this.items.length === 0
}
clear(){
this.items = []
}
size(){
return this.items.length
}
}
var s2 = new StackEs6()
2种实现对比
实例,10进制转2进制
- 十进制数是组成以10为基础的数字系统，有0，1，2，3， 4， 5， 6， 7， 8， 9十个基本数字组成
- 二进制数（binaries）是逢2进位的进位制，0、1是基本算符
var tenToTwo = function(number){
var s2 = new StackEs6()
var remainder //余数
var str = '';
while(number >0){
remainder = number%2
number =Math.floor(number/2)
s2.push(remainder)
}
while(s2.isEmpty() === false){
str+= s2.pop()
}
return str
}
栈的体现
function f1(){
return console.log('f1 finish')
}
function f2(){
f1()
return console.log('f2 finish')
}
