This is my code.
{program Ryan;
var
 n,i,k:integer;
 a:array[0..1000] of char;
 b:array[0..25] of 'a'..'z';
 c,d:array[0..1000] of integer;
begin
 for i:=0 to 25 do
 b[i]:=chr(i+97);
 i:=-1;
 repeat
  i:=i+1;
  read(a[i]);
  c[i]:=ord(a[i])-97;
  if (c[i]<26)and(i<>0)
  then while (c[i]<c[i-1])or (c[i]<26) do
       c[i]:=c[i]+26;
 until eoln;
 d[0]:=c[0]-5;
 for n:=0 to i do
 if n<>0
 then d[n]:=c[n]-c[n-1];
 for n:=0 to i do
 if d[n]>26
 then begin d:=c;   break;  end;
 while k<i+1 do
 begin
 write(b[d[k]]);
 k:=k+1;
 end;
end.}
And I have sth. didn't understand.
That is if I input 'asdffg',what is the output?
Or if I input 'ghhllz',what is the output?
Plz help me~