RosettaCodeData/Task/Number-names/Lua/number-names-1.lua

38 lines
1.2 KiB
Lua

words = {"one ", "two ", "three ", "four ", "five ", "six ", "seven ", "eight ", "nine "}
levels = {"thousand ", "million ", "billion ", "trillion ", "quadrillion ", "quintillion ", "sextillion ", "septillion ", "octillion ", [0] = ""}
iwords = {"ten ", "twenty ", "thirty ", "forty ", "fifty ", "sixty ", "seventy ", "eighty ", "ninety "}
twords = {"eleven ", "twelve ", "thirteen ", "fourteen ", "fifteen ", "sixteen ", "seventeen ", "eighteen ", "nineteen "}
function digits(n)
local i, ret = -1
return function()
i, ret = i + 1, n % 10
if n > 0 then
n = math.floor(n / 10)
return i, ret
end
end
end
level = false
function getname(pos, dig) --stateful, but effective.
level = level or pos % 3 == 0
if(dig == 0) then return "" end
local name = (pos % 3 == 1 and iwords[dig] or words[dig]) .. (pos % 3 == 2 and "hundred " or "")
if(level) then name, level = name .. levels[math.floor(pos / 3)], false end
return name
end
local val, vword = io.read() + 0, ""
for i, v in digits(val) do
vword = getname(i, v) .. vword
end
for i, v in ipairs(words) do
vword = vword:gsub("ty " .. v, "ty-" .. v)
vword = vword:gsub("ten " .. v, twords[i])
end
if #vword == 0 then print "zero" else print(vword) end