10 CLV:CLS:CLT:X=12:L=30
20 X=X-BTN(28)*(X>1)+BTN(29)*(X<25)
30 LC X,23:?CHR$(0,240,0);
40 LC 2+RND(25),0:?"*"
50 IF BTN(32) GSB 130
60 WAIT 3
70 SCROLL 31
80 T=TICK()/60
90 LC 0,23:?L-T;
100 LC 27,23:?S;
110 IF !SCR(X+1,23) && T<L GOTO 20
120 BEEP 30,30:?:CLK:END
130 B=X+1:C=23:H=0
140 IF C<23 LC B,C:?CHR$(0);
150 IF H S=S+1:BEEP:RTN
160 C=C-1
170 H=SCR(B,C)
180 LC B,C:?"|"
190 IF C>=0 GOTO 140
200 S=S-1:RTN