Wondering if anyone knew why this change calculator isn't working?

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Hello, just wondering if anyone could help me with my change calculator.
It's meant to figure out the least amount of coins to give back but it doesn't seem to be outputting right.
Any help would be greatly appreciated!

<br />
<html><br />
	<head><br />
		<script><br />
		<br />
			var $ = function(id){<br />
		<br />
				return document.getElementById(id);<br />
			}<br />
			const fiveChange = 5;<br />
			const tenChange = 10;<br />
			const twentyChange = 20;<br />
			const fortyChange = 40;<br />
			const fiftyChange = 50;<br />
			<br />
			<br />
			function calculateMinChange(){<br />
			<br />
			if (amount >= fiftyChange )<br />
			{<br />
				$("fiftyCents").value = 1;<br />
				amount = amount - 50;<br />
				return fiftyCents;<br />
			}<br />
			else if (amount >= fortyChange)<br />
			{<br />
				$("twentyCents").value = 2;<br />
				amount = amount - 40;<br />
				return twentyCents;<br />
			<br />
			}<br />
			else if (amount >= twentyChange)<br />
			{<br />
				$("twentyCents").value = 1;<br />
				amount = amount - 20;<br />
				return twentyCents;<br />
			<br />
			}<br />
			else if (amount >= tenChange)<br />
			{<br />
				$("tenCents").value = 1;<br />
				amount = amount - 10;<br />
				return tenCents;<br />
			<br />
			}<br />
			else (amount < fiveChange)<br />
			{<br />
				$("fiveCents").value = 1;<br />
				amount = amount - 5;<br />
				return fiveCents;<br />
			<br />
			<br />
			}<br />
			}<br />
				<br />
			function processEntries(){<br />
				var amount = parseInt($("amount").value);<br />
			<br />
				if (isNaN(amount) || amount>99){<br />
					alert("Change must be numeric and under 99")<br />
				<br />
				}<br />
					else{<br />
						calculateMinChange();<br />
						$("fiveCents").value= fiveCents;<br />
						$("tenCents").value= tenCents;<br />
						$("twentyCents").value= twentyCents;<br />
						$("fiftyCents").value= fiftyCents;<br />
						<br />
					}<br />
				<br />
				<br />
			}<br />
			<br />
			window.onload = function(){ //process click of calculation related to the button<br />
				$("calculate").onclick = processEntries;<br />
				$("amount").focus(); //blinks cursor<br />
			}<br />
			<br />
			<br />
		</script><br />
	<br />
	</head><br />
	<br />
	<body><br />
		<br />
			 Change Calculator  <br />
			<label for="amount">Enter number of cents (0-99).</label>	<br />
			<input type="text" id="amount"><br />
			<label> </label> <br />
			<input type="button" id="calculate" value="calculate"><br />
			<label for="fiveCents">Five cents:  </label><br />
			<input type="text" id="fiveCents"><br />
			<label for="tenCents">Ten cents:  </label><br />
			<input type="text" id="tenCents"><br />
			<label for="twentyCents">Twenty Cents:   </label><br />
			<input type="text" id="twentyCents"><br />
			<label for="fiftyCents">Fifty Cents:   </label><br />
			<input type="text" id="fiftyCents"><br />
			<br />
			<br />
	</body><br />
	<br />
</html><br />

What I have tried:

I have tried using alerts and debugging but not 100% sure on how to output the results or if i'm just doing it wrong.

Posted 13-Sep-16 14:05pm

Member 12721687

Updated 13-Sep-16 14:48pm

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Karthik_Mahalingam · Accepted Answer · 2016-09-13T14:48:00

$("fiveCents").value = fiveCents;
$("tenCents").value = tenCents;
$("twentyCents").value = twentyCents;
$("fiftyCents").value = fiftyCents;

These variable are not declared anywhere

Each condition in the function calculateMinChange(amount) { returns a variable as above which is not declared.
and the amount calculation is pointless, since you are not using it anywhere, so i thing you are trying to return the amount. you only will know the logic .

Correct the above, it should work.

Updated Solution

HTML

<html>
<head>
    <script>


        var $ = function (id) {
            return document.getElementById(id);
        }
        const fiveChange = 5;
        const tenChange = 10;
        const twentyChange = 20;
        const fortyChange = 40;
        const fiftyChange = 50;


        function calculateMinChange(amount) {

            if (amount >= fiftyChange) {
                $("fiftyCents").value = 1;
                amount = amount - 50;
                return amount;
            }
            else if (amount >= fortyChange) {
                $("twentyCents").value = 2;
                amount = amount - 40;
                return amount;

            }
            else if (amount >= twentyChange) {
                $("twentyCents").value = 1;
                amount = amount - 20;
                return amount;

            }
            else if (amount >= tenChange) {
                $("tenCents").value = 1;
                amount = amount - 10;
                return amount;

            }
            else (amount >= fiveChange)
            {
                $("fiveCents").value = 1;
                amount = amount - 5;
                return fiveCents;
            }
        }

        function processEntries() {
            $("fiveCents").value = 0;
            $("tenCents").value = 0;
            $("twentyCents").value = 0;
            $("fiftyCents").value = 0;

            var amount = parseInt($("amount").value);
            if (isNaN(amount) || amount > 99) {
                alert("Change must be numeric and under 99")

            }
            else {
                debugger


                while (amount >= 5)
                    amount = calculateMinChange(amount); 
                 
            }}


        window.onload = function () { //process click of calculation related to the button
            $("calculate").onclick = processEntries;
            $("amount").focus(); //blinks cursor
        }



    </script>

</head>

<body>

    Change Calculator
    <label for="amount">Enter number of cents (0-99).</label>
    <input type="text" id="amount">
    <label> </label>
    <input type="button" id="calculate" value="calculate">
    <label for="fiveCents">Five cents: </label>
    <input type="text" id="fiveCents">
    <label for="tenCents">Ten cents: </label>
    <input type="text" id="tenCents">
    <label for="twentyCents">Twenty Cents: </label>
    <input type="text" id="twentyCents">
    <label for="fiftyCents">Fifty Cents: </label>
    <input type="text" id="fiftyCents">


</body>

</html>