<script>
    var arr=[2,2,3,3,4,4,5,5,6,6]
    function norepeat(arr) {
        for (var i=0;i<arr.length;i++){
            for(var j=i+1;j<arr.length;j++){
                if (arr[i]==arr[j]){
                    arr.splice(j,1)
                }
            }
        }
        return arr
    }
    console.log(norepeat(arr))

</script>

 var arr=[1,18,2,3,23,4,4,5,5,6]
    var brr=[];
    function norepeat(arr) {
        for (var i=0;i<=arr.length;i++){
            if (arr[i]!=arr[i+1]){
                brr.push(arr[i])
            }
        }
        return brr
    }
    console.log(norepeat(arr))