Algorithm

for i = 0 to n-2 do {
	j <- random integer such that 0 <= j < n
	swap(a[i], a[j])
}

The “inside-out” Algorithm

for i = 0 to n-1 do {
	j <- random integer such that 0 <= j <= i
	swap(a[i], a[j])
}

The advantage of this technique is that n, the number of elements in the array, does not need to be known in advance

Time complexity:

Worst	Average	Best
$θ (N)$	$θ (N)$	$θ (N)$

Space complexity auxiliary:

Worst	Average	Best
$θ (1)$	$θ (1)$	$θ (1)$

Online: Yes, for “inside-out” version