шахматная доска в qbasic
SCREEN 9 Y = 20 FOR J = 1 TO 8 FOR I = 1 TO 8 X = X + 20 IF C = 4 THEN C = 14 ELSE C = 4 LINE (X, Y)-(X + 20, Y + 20), C, BF NEXT I Y = Y + 20 X = 0 IF C = 4 THEN C = 14 ELSE C = 4 NEXT J