10 CLS
20 COLOR 1
30 FOR I=10 TO 200 STEP 2
40 LINE (5,I)-(205,I)
50 LINE(I,5)-(I,205)
60 NEXT I
70 PAINT (5,10),2,0

10 CLS
20 COLOR 1
30 FOR I=2 TO 200
40 FOR J=2 TO 200
50 K=I MOD 4
60 L=J MOD 4
70 IF (K=L AND K<2) OR K*L=6 THEN PSET (I,J)
80 NEXT J
90 NEXT I
99 PAINT (0,0)

10 MODE 1
20 PEN 1
30 FOR i%=1 TO 25
40 PRINT STRING$(40,"u");
50 NEXT i%
60 LOCATE 1,1
70 MOVE 10,14
80 FILL 1

void fill (x, y, col) {
   plot (x, y, col)
   if (point (x + 1, y) != col then fill (x + 1, y, col);
   if (point (x, y + 1) != col then fill (x, y + 1, col);
   if (point (x - 1, y) != col then fill (x - 1, y, col);
   if (point (x, y - 1) != col then fill (x, y - 1, col);
}

typedef struct fillBufferT {
   int x1, x2;
};

fillBufferT buffer [vertical_res];