Step 1: Divide the number into separate digits:
09393 => 0 9 3 9 3
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
0 to 9 = 9
9 to 3 = 6
3 to 9 = 6
9 to 3 = 6
3 to 0 = 3
Step 3: Combine the filters to a string:
9 6 6 6 3 = 96663