You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2,5-dihydroxy-4-(1-hydroxyethenyl)benzoic acid;4-(1-hydroxyethenyl)-3,6-dioxocyclohexa-1,4-diene-1-carboxylic acid is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H14O10
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