var n = [
// using lowercase to represent Unicode lined Roman Numerals
[1000000, "m"],
[ 500000, "d"],
[ 100000, "c"],
[ 90000, "cm"],
[ 50000, "l"],
[ 10000, "x"],
[ 9000, "xc"],
[ 5000, "v"],
[ 4000, "iv"],
[ 1000, "M"],
[ 900, "CM"],
[ 500, "D"],
[ 100, "C"],
[ 90, "XC"],
[ 50, "L"],
[ 40, "XL"],
[ 10, "X"],
[ 9, "IX"],
[ 5, "V"],
[ 4, "IV"],
[ 1, "I"],
[ 0]
];

var output = [];
var i = 0, x = 0;
var arabic = 0;

function makeArabic(numbers) {
for (i = 0; numbers.length && n[i][0]; i++)
if (numbers.substring(0,n[i][1].length) == n[i][1]) {
arabic += n[i][0];
return makeArabic(numbers.substring(n[i][1].length));
}
return arabic;
}

makeArabic(“MCMXLIX”);

Quick variation on the 2 line makeChange algorithm to encode:

(does multi million conversions – though I can see how they’d read that fast enough to be of any use – can you picture the bailout being accounted for in roman numerals? How much graft do you think they’d be able to get away with using accounting sheets with:

all numbers in Ms: mdccccvMMDCCCLIX * mmmdccvMDCLIX ! : )

var n = [
// using lowercase to represent Unicode lined Roman Numerals
[1000000, "m"],
[ 500000, "d"],
[ 100000, "c"],
[ 90000, "cm"],
[ 50000, "l"],
[ 10000, "x"],
[ 9000, "xc"],
[ 5000, "v"],
[ 4000, "iv"],
[ 1000, "M"],
[ 900, "CM"],
[ 500, "D"],
[ 100, "C"],
[ 90, "XC"],
[ 50, "L"],
[ 40, "XL"],
[ 10, "X"],
[ 9, "IX"],
[ 5, "V"],
[ 4, "IV"],
[ 1, "I"],
[ 0]
];

var output = [];
var i = 0, x = 0;

function makeRoman(money) {
for (x = Math.floor(money / n[i][0]); x; x–)
output.push(n[i][1]);
return isNaN(n[i + 1]) ? makeRoman(money % n[i++][0]) : output;
}

makeRoman(17996).join(“”);