Question

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<pre>
    <code>
    Array.prototype.removeDuplicates=function () {
        var ret =[];
        this.forEach(function (item,index,array) {
            if(ret.indexOf(item)< 0){
                ret.push(item);
        }
        });
        return ret;
    };
    </code>
</pre>
<pre>
    <code>
    Array.prototype.removeDuplicates=function () {
        var ret =[];
        this.forEach(function (item,index,array) {
            if(ret.indexOf(item)< 0){
                ret.push(item);
        }
        });
        return ret;
    };
    </code>
</pre>