You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[(1S)-1-(3,4-difluorophenyl)ethyl]-N-methyl-2-oxo-1H-pyridine-3-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C15H14F2N2O2
assistant