Method for calculating cardinal number of random hybrid operation of intersection and union of private sets among three parties

The invention discloses a method for calculating a mixed operation cardinal number of a private set intersection and union set among three parties, which is mainly a method for calculating the mixed operation cardinal number of the intersection and union set among the participants without leaking the privacy of the participants under the assistance of the third party under the condition that the participants are not required to have complete quantum capability. Firstly, a third party prepares a Bell state and sends a second particle sequence to a participant, and a first particle sequence is reserved. And the participants encode and encrypt own private vectors on the received particle sequence, and return the private vectors to the third party. And after receiving the returned particle sequence, the third party detects whether an attacker exists, performs decryption calculation after confirming the security, finally obtains a private vector coded by the participant, and calculates and publishes any hybrid ope