function suber (name) {          this.name=name;          this.frend=["xx","yy"];        }        suber.prototype.sayName = function() {              alert(this.name);        };        function sub(name,age){            suber.call(this,name);            this.age=age;        }        function inheritPrototype (sub,suber) {          var prototype=Object(suber.ptototype);          prototype.constructor=sub;          sub.prototype=prototype;        }        inheritPrototype(sub,suber);        sub.prototype=new suber();        sub.prototype.sayName = function() {              alert(this.name+"xxxxxxxxx");        };        var su=new sub("sun zi",33);        su.frend.push(33);        // alert(su.frend.toString());        var suber=new suber("lao zi");        su.sayName();        suber.sayName()        // alert(suber.frend.toString()+"=  "+suber.sayName());