How to remove repeated entries from an array while preserving non-consecutive duplicates?

Question

I have an array like var arr = [5, 5, 5, 2, 2, 2, 2, 2, 9, 4, 5, 5, 5]; I really want the output to be [5,2,9,4,5]. My logic for this was:

Answer 1

if you are looking purely by algorithm without using any function

var arr = [5, 5, 5, 2, 2, 2, 2, 2, 9, 4, 5, 5, 5];

    function identical(array){

        var newArray = [];
        newArray.push(array[0]);
        for(var i = 0; i < array.length -1; i++) {
            if(array[i] != array[i + 1]) {
                newArray.push(array[i + 1]);
            }
        }
        console.log(newArray);
    }
    identical(arr);

Fiddle;