js用数组实现Stack

"use strict";

function Stack() {
this.dataStore = [];
this.stackSize = 0;
this.top = 0;
this.pop = pop;
this.push = push;
this.peek = peek;
this.clear = clear;
this.length = length;
this.empty = empty;
}

function pop() {
return this.dataStore[--this.top];
}

function push(element) {
this.dataStore[this.top++] = element;
}

function peek() {
return this.dataStore[this.top - 1];
}

function clear() {
delete this.dataStore;
this.dataStore = [];
this.top = 0;
}

function length() {
return this.top;
}

function empty() {
return this.top === 0;
}

console.log("test the Stack");
var stack = new Stack();
stack.push("hello");
stack.push("world");
console.log("stack length=" + stack.length() + ", isEmpty=" + stack.empty() + ", topElement=" + stack.peek());

stack.pop();
console.log("stack length=" + stack.length() + ", isEmpty=" + stack.empty() + ", topElement=" + stack.peek());