CS 161 - Introduction to Programming with PHP
<?php
// Display how many of a denomination of $value will be returned as
// change for $change, with the description of $single (when one)
// or $plural (for multiple). Use $single.'s' if $plural not specified.
//
function changeBack($change, $value, $single, $plural='') {
if ($plural=='') $plural=$single.'s'; // Default plural form
$count=floor(($change+0.009)/$value);
if ($count) { // Have at least one as change
echo " $count ".($count>1?$plural:$single)."\n";
}
return $change-$count*$value;
}
echo "Amount of purchase? ";
$purchase=trim(fgets(STDIN));
if ($purchase<=0) {
if ($purchase!='') {
echo "I couldn't understand \"$purchase\" as an amount\n";
} else {
echo "No purchase made; It's Miller Time.\n";
}
exit;
}
echo "Amount of payment? ";
$payment=trim(fgets(STDIN));
if ($payment<=0) {
if ($payment!='') {
echo "I couldn't understand \"$payment\" as an amount\n";
} else {
echo "No payment? Get outa' here, ya lousy bum.\n";
}
exit;
}
if ($payment<$purchase) {
echo "You want to finance the rest of that, Buddy?\n";
} else if ($payment==$purchase) {
echo "Exact change! Thank you!\n";
} else {
echo "You get ".($payment-$purchase)." in change as:\n";
$change=changeBack($payment-$purchase,5.0,'five');
$change=changeBack($change,1.0,'dollar');
$change=changeBack($change,0.25,'quarter');
$change=changeBack($change,0.10,'dime');
$change=changeBack($change,0.05,'nickel');
$change=changeBack($change,0.01,'penny','pennies');
}
?>