JS1k: The JavaScript code golfing competition

function B(e){this.x=0;this.y=0;this.radius=e;this.scaleX=1;this.scaleY=1;this.color="#000"}function cb(){var e=new B(M.random()*15);e.x=M.random()*wi;e.y=M.random()*h;e.m=e.radius;e.ox=M.random()*wi;e.oy=M.random()*h;bs.push(e)}function ani(e){if(!go){var t=mX-e.x,n=mY-e.y,r=M.sqrt(t*t+n*n)}else{var t=e.ox-e.x,n=e.oy-e.y,r=M.sqrt(t*t+n*n)}e.x+=t*ea;e.y+=n*ea;if(e.y+e.radius>h)e.y=h-e.radius;e.d(a)}var w=window,wi=w.innerWidth,h=w.innerHeight,mX=0,mY=0,g=.25,ea=.3,bs=[],go=false,M=Math;c.setAttribute("width",wi);c.setAttribute("height",h);b.style.margin="0px";B.prototype.d=function(e){e.save();e.translate(this.x,this.y);e.scale(this.scaleX,this.scaleY);e.fillStyle=this.color;e.beginPath();e.arc(0,0,this.radius,0,M.PI*2,true);e.closePath();e.fill();e.restore()};c.addEventListener("mousemove",function(e){mX=e.pageX;mY=e.pageY;cb()},false);c.addEventListener("mousedown",function(){go=!go},false);(function e(){a.clearRect(0,0,c.width,c.height);bs.forEach(ani);setTimeout(e,30)})()

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