itoa.js

var dict = ["a", "s", "d", "f"]

itoa = function (n) {
	retstr = ""
	while (n !== 0) {
		digit = dict[(n % (dict.length + 1)) - 1]

		retstr = digit + retstr

		n = Math.floor(n / dict.length)
		if (n === 1) {
			n = 0
		}
	}
	return retstr
}

console.log(itoa(1))
console.log(itoa(2))
console.log(itoa(3))
console.log(itoa(4))
console.log(itoa(5))
console.log(itoa(6))
console.log(itoa(7))
console.log(itoa(8))
console.log(itoa(9))
console.log(itoa(10))

This is supposed to print out:
a
s
d
f
aa
as
ad
af
etc..