You cannot mix ISPP and CODE section codes.
Try like this:
Code:
#define public RequiredSpace "1000"
#define MbToBytes(str Value) \
Int(Value, 0) * 1024 * 1024
[Setup]
AppName=111
AppVersion=0.0
AppPublisher=bbbbb
DefaultDirName={autopf}\111
ExtraDiskSpaceRequired={#MbToBytes(RequiredSpace)}