Step 1: Divide the number into separate digits:
02245 => 0 2 2 4 5
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
0 to 2 = 2
2 to 2 = 0
2 to 4 = 2
4 to 5 = 1
5 to 0 = 5
Step 3: Combine the filters to a string:
2 0 2 1 5 = 20215