if (!Array.prototype.push) Array.prototype.push=new Function ("elem","for(var i=0;i<arguments.length;i++) this[this.length]=arguments[i];");
if (!Array.prototype.pop) Array.prototype.pop=new Function ("elem","var x = this[this.length-1]; this.length--; return x;");
if (!Array.prototype.shift) Array.prototype.shift=new Function ("var x = this[0]; for(var i=1;i<this.length;i++) this[i-1]=this[i]; this.length--; return x;");
if (!Array.prototype.unshift) Array.prototype.unshift=new Function ("ne"," for(var i=this.length;i>0;i--) this[i]=this[i-1]; this.length--; this[0]=ne;");