var arr=[112,112,56,'hello',112,112,56,'hello','str1','str']
Arrary.prototype.chongfu=function(){
var res=[];
var json={};
for(var i=0;i<this.lengh;i++){
if(!json[this[i]]){
res.push(this[i]);
json[this[i]]=1;
}
}
return res;
}
alert(arr.chongfu());