text: (function(){var main;main=function(opt){opt==null&&(opt={});this.opt=opt;this.stack=[];this.step=opt.step||1;return this};main.prototype=import$(Object.create(Object.prototype),{add:function(v,s){s==null&&(s=0);if(!(this.value!=null)){this.value=v}v=this.step>0?Math.max(this.value,v):Math.min(this.value,v);v=v+(this.step>0?1:-1)*Math.max(Math.abs(this.step),Math.abs(s));this.stack.push(v);this.value=v;return v},remove:function(v){var i;if(!~(i=this.stack.indexOf(v))){return}return this.stack.splice(i,1)}});if(typeof window!="undefined"&&window!==null){window.zmgr=main}if(typeof module!="undefined"&&module!==null){module.exports=main}function import$(obj,src){var own={}.hasOwnProperty;for(var key in src)if(own.call(src,key))obj[key]=src[key];return obj}}).call(this);
  