procedure main(A)
    every writes(" ",nth(0 to 25) | "\n")
    every writes(" ",nth(250 to 265) | "\n")
    every writes(" ",nth(1000 to 1025) | "\n")
end

procedure nth(n)
    return n || ((n%10 = 1, n%100 ~= 11, "st") |
                 (n%10 = 2, n%100 ~= 12, "nd") |
                 (n%10 = 3, n%100 ~= 13, "rd") | "th")
end