  In a recent paper (Int. J. Quantum Inf. 17 (2019) 1950026), the authors
discussed the shortcomings in the security of a quantum private comparison
protocol that we previously proposed (Int. J. Quantum Inf. 15 (2017) 1750014).
They also proposed a new protocol aimed to avoid these problems. Here we
analysis the information leaked in their protocol, and find that it is even
less secure than our protocol in certain cases. We further propose an improved
version which has the following advantages: (1) no entanglement needed, (2)
quantum memory is no longer required, and (3) less information leaked.
Therefore, better security and great feasibility are both achieved.
