const cocktailSort = arr => {
    let isSorted = true;

    while (isSorted){
        for (let i=0; i< arr.length-1; i++){
            if (arr[i] > arr[i+1]){
                let temp = arr[i];
                arr[i] = arr[i+1];
                arr[i+1] = temp;
                isSorted = true;
            }
        }

        if (!isSorted) break;
        isSorted = false;

        for (let j=arr.length-1; j>0; j--){
            if (arr[j-1] > arr[j]){
                let temp = arr[j];
                arr[j] = arr[j-1];
                arr[j - 1] = temp;
                isSorted = true;
            }
        }
    }
    return arr

}