10 Hgr
15 Hcolor = 3
20 let xa=140 : let ya=0
30 let xb=0 : let yb = 159
40 let xc=279 : let yc = 159
50 Hplot xa,ya : Hplot xb,yb : Hplot xc,yc
60 let x=INT(rnd(1)*40) : LET Y = INT(RND(1)*40)
70 HPLOT X,Y
80 D=(INT(RND(1)*3)) + 1
85 PRINT D
90 ON D GOTO 100,200,300
100 X=INT((X + XA)/2) : Y=INT((Y + YA)/2)
110 GOTO 70
200 X=INT((X + XB)/2) : Y=INT((Y + YB)/2)
210 GOTO 70
300 X=INT((X + XC)/2) : Y=INT((Y + YC)/2)
310 GOTO 70