Примеры программ на языке QBASIC

DEFINT A-Z
SCREEN 12
x0 = 10: y0 = 10: col = 8: w = 50
FOR y = y0 TO y0 + 7 * w STEP w
 col = 15 - col
 FOR x = x0 TO x0 + 7 * w STEP w
   LINE (x, y)-(x + w, y + w), col, BF
   LINE (x, y)-(x + w, y + w), 15, B
   col = 15 - col
 NEXT x
NEXT y