Implement Bubble Sort

{
"arr": [5, 8, 3, 9, 4, 1, 7]
}

[1, 3, 4, 5, 7, 8, 9]

function swapArr(arr, i, j) {
    var tempArr = arr[i];
    arr[i] = arr[j];
    arr[j] = tempArr;
}

function bubble_sort(arr) {
    // Write your code here.
    for(var i=0; i< arr.length; i+= 1){
        for(var j=1; j < arr.length; j+=1) {
            if(arr[j-1] > arr[j]) {
                swapArr(arr, j-1, j);
            }
        }
    }
    return arr;
}