Each step of the procedure can be represented as an operation on the stacks. The operation can be performed by removing the specified number of crates from the source stack and adding them to the destination stack. The top crate of each stack can be tracked as the operation is performed to determine the final configuration.
Most of the complexity is in parsing the input data:
- Initialize empty lists for the stacks of crates and the rearrangement steps. Split the input into lines.
- Parse the stacks of crates by splitting each line into individual characters and adding each stack of crates to the list of stacks.
- Skip the empty line in the input.
- Parse the rearrangement steps by splitting each line into words, converting the words to integers, and adding each step to the list of steps.
- Return the lists of stacks and steps.
Instead of simply removing the specified number of crates from the source stack and adding them to the destination stack, the crates must be removed from the source stack in the order that they appear and added to the destination stack in that same order.