Indetectables

function asc(letras:string):integer;
begin
   if length(letras)>=1 then
      result:=ord(letras[1])
   else
     result:=0;
end;

function sCipher(text,key:string):string;
var
i,j,seed:integer;
sfinal:String;
begin
   sfinal:=''; seed:=0;

   for i :=1  to  length(key) do
   begin
     seed:=(seed+asc(key)) * length(key);
     key:=AnsiMidStr(key,2,length(key)-1);
   end;

   for j:=1 to length(text) do
   begin
     sfinal:=sfinal+IntToStr((ord(text[1])+seed));
     text:= AnsiMidStr(text,2,length(text));
   end;

   result:=sfinal;
end;


function sUnCipher(text,key:string):string;
var
seed,step,tamano,i,j:integer;
sfinal:string;
begin
   seed:=0; sfinal:='';

   for i :=1  to length(key) do
   begin
     seed:=(seed+asc(key))*length(key);
     key:=AnsiMidStr(key,2,length(key)-1);
   end;

   step:=length(inttostr(seed));
   j:=step;
   tamano:=length(text);

   while(j<=tamano) do
   begin
      sfinal:=sfinal+chr(strtoint(AnsiLeftStr(text,step))-seed);
      text:= AnsiMidStr(text,step+1,length(text));
      j:=j+step;
   end;
   result:=sfinal;
end;