You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 3-[1-[[2-fluoro-5-(trifluoromethyl)phenyl]methyl]piperidin-4-yl]-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine;hydrochloride is given. What is its corresponding molecular formula?
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C18H22ClF4N5
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