The task is to create 1 pixel wide coloured vertical pinstripes with a sufficient number of pinstripes to span the entire width of the graphics display.



The pinstripes should either follow the system palette sequence,   or a sequence that includes:

black,   red,   green,   blue,   magenta,   cyan,   yellow,   and   white:

   after filling the top quarter, switch to a wider 2 pixel wide vertical pinstripe pattern,
   halfway down the display, switch to 3 pixel wide vertical pinstripe,
   finally to a 4 pixels wide vertical pinstripe for the last quarter of the display.


See also

   display black and white 
   print colour


SCREEN 12
w = 640: h = 480
 
h = h / 4
y2 = h - 1
 
FOR i = 1 TO 4
    col = 0
    y = (i - 1) * h
    FOR x = 1 TO w STEP i
        IF col MOD 15 = 0 THEN col = 0
        LINE (x, y)-(x + i, y + h), col, BF
        col = col + 1
    NEXT x
NEXT i