Step 1: Divide the number into separate digits:
32318 => 3 2 3 1 8
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
3 to 2 = 1
2 to 3 = 1
3 to 1 = 2
1 to 8 = 7
8 to 3 = 5
Step 3: Combine the filters to a string:
1 1 2 7 5 = 11275