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Javascript麻瓜： 便利商店買東西，零錢夠不夠

For Javascript Muggle: Are your changes enough for buying a good in convenience store (exercise and codes sample)


Please apply what you have learned from the following pages to check if you have enough changes in your pocket to buy a good in a convenience store.
name of good
cost to buy
pennies ($0.01)
nickels 
($0.05)
dimes
($0.1)
quarters
($0.25)
a
$3
6
25
30
10
b
$10
0
24
15
3
c
$25
3
85
1
150
d
$15
20
0
250
48
e
$8
35
37
1
5

Your codes should be able to print the following output to the console:
  • Good name: a, Cost: 3, Buy? YES
  • Good name: b, Cost: 10, Buy? NO
  • Good name: c, Cost: 25, Buy? YES
  • Good name: d, Cost: 15, Buy? YES
  • Good name: e, Cost: 8, Buy? NO
  •  
Thefollowing sample codes has applied "Object Oriented Javascript', "Inheritance', and 'Function Context'.


/ apply https://www.learn-js.org/en/Object_Oriented_JavaScript

let Pocket=function(){};

Pocket.prototype.initialize = function (penny, nickel, dime, quarter) 
{
    this.penny=0.01*penny;
    this.nickel=0.05*nickel;
    this.dime=0.2*dime;
    this.quarter=0.25*quarter;
    this.changestotal=this.penny+this.nickel+this.dime+this.quarter;
};

//apply https://www.learn-js.org/en/Inheritance
let CheckEnoughChanges = function(){};
CheckEnoughChanges.prototype = new Pocket();
CheckEnoughChanges.prototype.good = function(name, cost) 
{
    this.goodName=name;
    this.goodCost=cost;
};

let good = new CheckEnoughChanges();

//apply https://www.learn-js.org/en/Function_Context

var boundCompareCost=compareCost.bind(good);

function compareCost() 
{
if (this.changestotal >= this.goodCost) console.log('Good name: '+this.goodName+', '+'Cost: '+this.goodCost+', '+'Buy? '+'YES');
else console.log('Good name: '+this.goodName+', '+'Cost: '+this.goodCost+', '+'Buy? '+'NO');
};

//check good a
good.initialize(6,25,30,10);
good.good('a', 3);
boundCompareCost();

//check good b
good.initialize(0,24,15,3);
good.good('b', 10);
boundCompareCost();

//check good c
good.initialize(3,85,1,150);
good.good('c', 25);
boundCompareCost();

//check good d
good.initialize(20,0,250,48);
good.good('d', 15);
boundCompareCost();

//check good e
good.initialize(35,37,1,5);
good.good('e', 8);
boundCompareCost();



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