Complex sentence: Each locomotive class was given a number 0-9 that signified its power, 0 for the least powerful and 9 for the most, with a suffix of F or P, indicating freight and passenger roles respectively.
Split into simpler sentences: Each locomotive class was given a number 0-9 that signified its power, 0 for the least powerful and 9 for the most. They were then given a basic suffix of F or P indicating freight and passenger roles respectively.