function passDecrypt(s:string):string;
var
i:integer;
begin
result:='';
i:=length(s);
while i > 0 do
begin
if s[i] < #70 then
begin
result:=result+char((ord(s[i-1])-40) shl 4+ord(s[i-2])-40);
dec(i,2);
end;
dec(i);
end;
end;