Step 1: Divide the number into separate digits:
5654 => 5 6 5 4
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
5 to 6 = 1
6 to 5 = 1
5 to 4 = 1
4 to 5 = 1
Step 3: Combine the filters to a string:
1 1 1 1 = 1111