Step 1: Divide the number into separate digits:
49910 => 4 9 9 1 0
Step 2: Calculate the distance between each digit and the next (the last digit with the first):
4 to 9 = 5
9 to 9 = 0
9 to 1 = 8
1 to 0 = 1
0 to 4 = 4
Step 3: Combine the filters to a string:
5 0 8 1 4 = 50814