數組去重

</pre>有時一些簡單的代碼總是過一段時間就忘了，特此記下：</p><p><pre name="code" class="html"><script>
        var arr1=[1,2,3,3,3,4,5,6,6,6,7,8,8,8],arr2=[];
        for(var i=0; i<arr1.length; i++){
            if(arr2.indexOf(arr1[i])<0){
                arr2.push(arr1[i]);
            }
        }
        
        document.write(arr2);
    </script>
<br>
    <script>
    var arr1=[1,2,3,4,5,5,5,6,6,6,7,8],arr2=[];
    for(var i in arr1){
        if(arr2.indexOf(arr1[i])<0){
            arr2.push(arr1[i]);
        }
    }
    document.write(arr2);
    </script>  
<br>
    <script>
    var arr1=[1,1,1,2,3,4,4,4,5,6],
    arr2=[];
    for(var i=0,len=arr1.length; i<len; i++){
        if(arr2.indexOf(arr1[i])==-1){
            arr2.push(arr1[i]);
        }
    }
    document.write(arr2);
    </script>

function dedupe(array) {         
 	return Array.from(new Set(array));
}     
 console.log(dedupe([1, 2, 2, 3]));  // 1, 2, 3
 document.write(dedupe([1, 2, 2, 3]));