5 CLS:CLT
10 D=28
15 LET [28],29,28,31,30
20 K=INKEY()
30 IF K>27 AND K<32 D=[K]
40 SCROLL D
42 IF SCR(15,12)=42 GOTO 70
45 LC 15,12:?"O"
46 X=3+24*(D=28)+RND(24)*(D>29)
47 Y=RND(24)*(D<30)+24*(D=30)
48 LC X,Y:?"*";
50 WAIT 3
60 GOTO 20
70 LC 0,0:?TICK()/60
80 BEEP 30,30