“…In this protocol, secrets are divided into multiple groups, which improves efficiency by eliminating the need to compare all groups of information. Since then, different QPC protocols have been continuously proposed, aiming to determine the relationship between private and these studies mainly utilize various quantum states, including single photons [ 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 ], Bell states [ 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ], entangled states [ 34 , 35 , 36 , 37 , 38 , 39 ], cluster states [ 40 , 41 , 42 , 43 , 44 , 45 ] and d-level quantum states [ 46 , 47 , 48 , 49 ] as quantum resources. They also employ different quantum technologies, such as entanglement swapping and unitary operations, as well as determine whether to distribute keys for sharing secret keys to accomplish the comparison.…”