function ballToBallDetection(b1, b2) {

        //set the speed variables

        var xspeed1 = _root.yiff[b1].xspeed;

        var yspeed1 = _root.yiff[b1].yspeed;

        var xspeed2 = _root.yiff[b2].xspeed;

        var yspeed2 = _root.yiff[b2].yspeed;

        //set the position variables

        var xl1 = _root.yiff[b1].xpos;

        var yl1 = _root.yiff[b1].ypos;

        var xl2 = _root.yiff[b2].xpos;

        var yl2 = _root.yiff[b2].ypos;

        //define the constants

        var R = _root.yiff[b1].radius + _root.yiff[b2].radius;

        var a = -2 * xspeed1 * xspeed2 + xspeed1 * xspeed1 + xspeed2 * xspeed2;

        var b = -2 * xl1 * xspeed2 - 2 * xl2 * xspeed1 + 2 * xl1 * xspeed1 + 2 * xl2 * xspeed2;

        var c = -2 * xl1 * xl2 + xl1 * xl1 + xl2 * xl2;

        var d = -2 * yspeed1 * yspeed2 + yspeed1 * yspeed1 + yspeed2 * yspeed2;

        var e = -2 * yl1 * yspeed2 - 2 * yl2 * yspeed1 + 2 * yl1 * yspeed1 + 2 * yl2 * yspeed2;

        var f = -2 * yl1 * yl2 + yl1 * yl1 + yl2 * yl2;

        var g = a + d;

        var h = b + e;

        var k = c + f - R * R;

        //solve the quadratic equation

        var sqRoot = Math.sqrt(h * h - 4 * g * k);

        var t1 = (-h + sqRoot) / (2 * g);

        var t2 = (-h - sqRoot) / (2 * g);

        if (t1 > 0 && t1 <= 1) {

                var whatTime = t1;

                var ballsCollided = true;

        }

        //trace(t1 + "  " + t2);               

        if (t2 > 0 && t2 <= 1) {

                if (whatTime == null || t2 < t1) {

                        var whatTime = t2;

                        var ballsCollided = true;

                }

        }

        if (ballsCollided) {

                //Collision has happened, so throw a trace

                ball2BallReaction(b1, b2, xl1, xl2, yl1, yl2, whatTime);

        }

}

for (var i = 20; --i; ) {

        for (var j = i; --j; ) {

                //проверка столкновения шара i с шаром j

        }

}