SMILES, SELFIES, and BRICS are alphanumeric representations of variable length, incompatible with ML models. Therefore, they must be tokenized (i.e., converted into numeric representations) and "padded" so that all vectors are of the same size. Tokenizing creates a mapping between the unique symbols in a representation and integer values. The mapping is used as a reference for encoding each individual molecule. In order to achieve a consistent length across the dataset, the tokenized sequences were adjusted to the length of the longest sequence by post-padding with the appropriate amount of zeros.