Zigzag

Author: issalig
Category: The Main Challenge
System:   Amstrad CPC
Language: BASIC
Len source code: 137
Len exe file:   1024 (CPC minimum)
Len code only:   154
Instructions:
Install RetroVirtualMachine or WinAPE
Insert disk ccc.dsk
Then in BASIC type: RUN "CCC
Description:
3 zigzag lines and their reflections are drawn (aka 3 rectangles)
this is done 3 times resulting in a 3x3 grid
zigzag is done by ascending and descending changing direction when (x mod 3)==0

Comments:
I tried to make as small as possible but readable.