JavaScript - Stacks(Pez dispenser, colors)

Data Structures and Algorithms With Javascript
(O'Reilly Media)
Michael McMillan(著)

開発環境

• OS X Yosemite - Apple (OS)
• Emacs (Text Editor)
• JavaScript (プログラミング言語)
• SpiderMonkey (JavaScript engine)

Data Structures and Algorithms With Javascript (Michael McMillan(著)、O'Reilly Media)のChapter 4(Stacks)、Exercises 3.(No. 2801)を解いてみる。

Exercises 3.(No. 2801)

JavaScript(Emacs)

/*jslint         browser : true, continue : true,
  devel  : true, indent  : 4,    maxerr   : 50,
  newcap : true, nomen   : true, plusplus : false,
  regexp : true, sloppy  : true, vars     : false,
  white  : false
*/

/*global print */
var Stack,
    pez_dispenser,
    temp_stack,
    colors,
    len,
    i,
    elem;

Stack = function () {
    this.data_store = [];
    this.top = 0;
};
Stack.prototype.push = function (element) {
    this.data_store[this.top] = element;
    this.top += 1;
    return this;
};
Stack.prototype.peak = function () {
    return this.data_store[this.top - 1];
};
Stack.prototype.pop = function () {
    this.top -= 1;
    return this.data_store[this.top];
};
Stack.prototype.clear = function () {
    this.top = 0;
    this.data_store.length = 0;
};
Stack.prototype.length = function () {
    return this.top;
};
Stack.prototype.display = function () {
    var result = '',
        i,
        max = this.length();

    for (i = 0; i < max; i += 1) {
        result += this.data_store[i] + ' ';
    }
    print(result);
};

pez_dispenser = new Stack();
colors = ['red', 'yellow', 'white'];
len = colors.length;
for (i = 0; i < 10; i += 1) {
    pez_dispenser.push(colors[Math.floor(Math.random() * len)]);
}
pez_dispenser.display();
temp_stack = new Stack();
while (pez_dispenser.length() !== 0) {
    elem = pez_dispenser.pop();
    if (elem !== 'yellow') {
        temp_stack.push(elem);
    }
}
while (temp_stack.length() !== 0) {
    pez_dispenser.push(temp_stack.pop());
}
pez_dispenser.display();

出力結果(Terminal, shell, SpiderMonkey)

$ js sample3.js
white red white red red yellow yellow red white yellow 
white red white red red red white 
$ js sample3.js
white white white red yellow white red red yellow red 
white white white red white red red red 
$ js sample3.js
yellow red yellow white red red yellow yellow yellow red 
red white red red red 
$ js sample3.js
yellow white white yellow red red red white yellow red 
white white red red red white red 
$ js sample3.js
white red yellow yellow yellow yellow red red red yellow 
white red red red red 
$