My attempt at solving https://icpcarchive.ecs.baylor.edu/external/45/4574.pdf in Lua. This is my first Lua script.

prob4574.lua

#!/usr/bin/lua

local values = io.read("*number")

while values > 0 do
    local currentguess = 0

    for i = 1, values do
        thisguess = io.read("*number")
        if thisguess ~= currentguess then
            io.write(string.format("%d ", thisguess))
            currentguess = thisguess
        end
    end
    print("$")

    -- read values for the next loop
    values = io.read("*number")
end