4-6对数组去重

1.对数组遍历

    <script>
        var arr=[1,2,1,2,4,6];
        var res=[];
        arr.forEach(item=>{
            if(!res.includes(item)){
                res.push(item);
            }
        })
        console.log(res);
   </script>

set方法

 <script>
        var arr=[1,2,3,4,3,2];
        var s=new Set(arr);
        console.log(s);
        console.log([...s]);
    </script>