mxGraph.prototype.findTreeRoots=function(a,b,c){b=null!=b?b:!1;c=null!=c?c:!1;var d=[];if(null!=a){for(var e=this.getModel(),f=e.getChildCount(a),g=null,k=0,l=0;l<f;l++){var m=e.getChildAt(a,l);if(this.model.isVertex(m)&&this.isCellVisible(m)){for(var n=this.getConnections(m,b?a:null),p=0,q=0,r=0;r<n.length;r++)this.view.getVisibleTerminal(n[r],!0)==m?p++:q++;(c&&0==p&&0<q||!c&&0==q&&0<p)&&d.push(m);n=c?q-p:p-q;n>k&&(k=n,g=m)}}0==d.length&&null!=g&&d.push(g)}return d};