10 REM Magnus Jacobsson -80 20 RANDOMIZE 30 GOSUB 50 40 GOTO 80 50 ; CHR$(12) 60 FOR I%=0% TO 23% : ; CUR(I%,0%)CHR$(151%); 70 NEXT I% : RETURN 80 L%=1 : K%=1 90 A%(1%)=INT(RND*3%+1%)*2%+1% 100 A%(2%)=INT(RND*3%+1%)*2%+1% 110 IF A%(1%)=A%(2%) THEN 100 120 A%(3%)=INT(RND*3%+1%)*2%+1% 130 IF A%(1%)=A%(3%) OR A%(2%)=A%(3%) THEN 120 140 T%=1% 150 Y%=A%(T%) : GOSUB 180 160 T%=T%+1% : IF T%=4% THEN T%=1% : IF M%=1% THEN M%=0% : GOTO 90 ELSE M%=1% : GOTO 90 ELSE GOTO 150 170 STOP 180 X%=0% 190 Y%=Y%+L% : X%=X%+K% 200 IF X%<0% K%=1% : X%=0% 210 IF Y%>79% L%=-1% : Y%=79% 220 IF X%>71% K%=-1% : X%=71% 230 IF Y%<2% L%=1% : Y%=2% 240 IF M%=0% THEN IF DOT(X%,Y%) THEN RETURN 250 IF M%=1% THEN IF NOT (DOT(X%,Y%)) THEN RETURN 260 IF M%=0% THEN SETDOT X%,Y% ELSE CLRDOT X%,Y% 270 GOTO 190