fun readfile () = readfile []
           | x = let val ln = readln ()
                 in if eof ln then
                      rev x
                    else
                      readfile ` ln :: x
                 end

local	
	val lower_a = ord #"a";
	val lower_z = ord #"z";
	val upper_a = ord #"A";
	val upper_z = ord #"Z";

	fun which
			(c_upper c) = (upper_a, upper_z)
		|	_	    = (lower_a, lower_z)
		;
	
	fun scale
			(c, az) where (c > #1 az) = scale( (#0 az + (c - #1 az - 1)), az)
		|	(c, az) 		  = c
			
in
	fun encipher
			([], offset, t)                             = implode ` rev t
		|	(x :: xs, offset, t) where (c_alphabetic x) = encipher (xs, offset, (chr ` scale (ord x + offset, which x)) :: t)
		|	(x :: xs, offset, t)                        = encipher (xs, offset, x :: t)
		|	(s, offset) 				    = if (offset < 0) then
									encipher (explode s, 26 + (offset rem 26), [])
								      else
									encipher (explode s, offset rem 26, [])
end

fun default
		(false, y) = y
	|	(x,     _) = x

;
map println ` map (fn s = encipher (s,ston ` default (argv 0, "1"))) ` readfile ();