1. An information processing method comprising: receiving an input of matching information encrypted with an encryption algorithm allowing a Hamming distance to be calculated with the matching information encrypted, using a processor; calculating a first Hamming distance between the received matching information and registered information that is different from encrypted registered information of a user, the registered information being encrypted with the encryption algorithm and a second Hamming distance between the received matching information and the registered information of the user, using the processor; and determining that a user corresponding to the matching information is the user corresponding to the registered information when the calculated first Hamming distance falls into a distance distribution representing matches with another person that is different from the user and the calculated second Hamming distance falls into a distance distribution representing matches with the user, using the processor.