10 CLV:CLS
20 DRAW 0,0,62,0
30 DRAW 0,0,0,44
40 DRAW 62,0,62,44
50 DRAW 0,44,62,44
120 FOR Y=2 TO 42 STEP 2
130 FOR X=2 TO 60 STEP 2
140 DRAW X,Y
145 'IF !INKEY() CONT
150 R=RND(4)
160 A=0:B=0
170 IF R=0 A=-1
171 IF R=1 A=1
172 IF R=2 IF Y=2 B=-1 ELSE GOTO 150
173 IF R=3 B=1
175 IF POINT(X+A,Y+B) GOTO 150
180 DRAW X+A,Y+B
190 'IF !INKEY() CONT
200 NEXT
210 NEXT
300 X=1:Y=1:CLT
305 DRAW X,Y,0
310 U=X-BTN(28)+BTN(29)
320 V=Y-BTN(30)+BTN(31)
325 DRAW X,Y,1
330 LC 0,23:?TICK()/60;
340 C=POINT(U,V)
350 IF C GOTO 310
360 DRAW X,Y,0
370 X=U:Y=V
380 DRAW X,Y,1
390 WAIT 6
400 IF X!=61 || Y!=43 GOTO 305
410 LC 0,0:CLK:OK 2
420 END