Step 1: Divide the number into separate digits:
6008 => 6 0 0 8
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
6 to 0 = 6
0 to 0 = 0
0 to 8 = 8
8 to 6 = 2
Step 3: Combine the filters to a string:
6 0 8 2 = 6082