Xdepart2 = 10: Ydepart2 = 200
    largeurecran = 600: hauteurecran = 450
    pasX = 1: pasX2 = 1
    pasY = 1: pasY2 = 1
    Ycercle = Ydepart: Xcercle = Xdepart
    Ycercle2 = Ydepart2: Xcercle2 = Xdepart2
    rayon = 30: rayon2 = 30
    SCREEN 12

DO

    CIRCLE (Xold, Yold), rayon, 0
    CIRCLE (Xcercle, Ycercle), rayon, 3
    Xold = Xcercle: Xcercle = Xcercle + pasX

    IF (Xcercle >= largeurecran) OR (Xcercle <= 0) THEN
        pasX = -pasX
    END IF
   
    Yold = Ycercle: Ycercle = Ycercle + pasY
    IF (Ycercle >= hauteurecran) OR (Ycercle <= 0) THEN
        pasY = -pasY
    END IF
   
    CIRCLE (Xold2, Yold2), rayon2, 0
    CIRCLE (Xcercle2, Ycercle2), rayon2, 12
    Xold2 = Xcercle2: Xcercle2 = Xcercle2 + pasX2

    IF (Xcercle2 >= largeurecran) OR (Xcercle2 <= 0) THEN
        pasX2 = -pasX2
    END IF
   
    Yold2 = Ycercle2: Ycercle2 = Ycercle2 + pasY2
       
    IF (Ycercle2 >= hauteurecran) OR (Ycercle2 <= 0) THEN
        pasY2 = -pasY2
    END IF

    IF (rayon + rayon2) ^ 2 >= (Ycercle2 - Ycercle) ^ 2 + (Xcercle2 - Xcercle) ^ 2 THEN
        pasY2 = -pasY2: pasX2 = -pasX2
        pasY = -pasY: pasX = -pasX
    END IF

    FOR tempo = 1 TO 10000: NEXT

LOOP UNTIL INKEY$ = CHR$(27)