What code does Liu Jianming, played by Andy Lau, type at the end of "Infernal Affairs 3"? How to translate it?

It means "I'm sorry, Mary".

Liu Jianming is the protagonist in the "Infernal Affairs" trilogy, played by Andy Lau in middle age and Edison Chen in his youth. Liu Jianming grew up in a housing estate, joined the underworld when he was young and ignorant, and later joined the police force under the instructions of the underworld's eldest brother Han Chen.

Liu Jianming’s classic saying is: Give me a chance, I just want to be a good person.

Liu Jianming’s experience

Over the years, Liu has worked tirelessly in the police force, and with Han Chen’s support behind him, he has provided a lot of criminal information about the enemy’s underworld, which made Liu’s career in the police force He rose through the ranks within the team and was promoted to senior inspector year after year. But since the undercover incident was exposed, Liu Jianming has been under great pressure from Han Chen. Liu has silently conceived a plan in his mind to cleanse his own identity. Han Chen is his biggest obstacle, but he is determined to become a good policeman.