DETERMINATION DEVICE, DETERMINATION PROGRAM, AND DETERMINATION METHOD

A control unit of a determination device obtains a plurality of pieces of first data and second data, derives determination data based on the first data, specifies, from among a plurality of combinations of identifiers for respectively identifying the pieces of first data and an identifier for identifying the second data, based on the second data and the determination data, a valid combination including the identifiers of valid first data and second data, and an invalid combination including the identifiers of invalid first data or second data, and determines, based on a plurality of identifiers included in the specified invalid combination and a plurality of identifiers included in the valid combination, whether the first data or the second data is invalid.