Film and Television: My Cheat Code is AI

Back at the police station, Zhang Yang had just sat down at his desk and was drinking tea when Old Zheng came out with an invitation in his hand and said, "Everyone, come and see! This show is getting bigger and bigger. Let's chip in!"

Tian Rui took the invitation with a smile and asked, "Who is it?" Then, looking at the words on it, her face immediately fell. She replied, "Liao Jiangqun, Dong Yinglu."

"This is blatant provocation against our public security organs." Then, looking at Ji Jie, he said, "Liao Jiangqun has ordered the entire sixth team to attend her wedding."

Ji Jie took the invitation, looked at it, and said, "Let's go, we'll all go."

Zhang Yang said, "I can find a way to hack into their computer and see if there's any elevator program on it. Even if I delete it, I can recover it."

Old Zheng said, "Is...this kind of behavior legal?"

Zhang Yang thought for a moment and then shook his head. Ji Jie said, "Think about your own status, and don't talk about such unreliable things."

"Let's go to this wedding and see what Liao Jiangqun is trying to say. We'll all go."

On the 18th, the group of six went to the address on the invitation.

After arriving at their destination and getting out of the car, Zhang Yang looked around and said, "It seems Dong Yinglu already knows what we're investigating. This marriage is off the table."

Upon entering the banquet hall, there were no other guests except Liao Jiangqun, who stood there in a white wedding dress with a flower pinned to her chest that read "Bride".

Upon seeing everyone arrive, Liao Jiangqun's expression changed slightly. Ji Jie stepped forward, and Liao Jiangqun shook his head, saying, "Dong Yinglu knows everything. There's no groom, nothing at all."

Liao Jiangqun took a deep breath and said, "I killed him, and this is the evidence." He then took out a key and handed it to Ji Jie.

"After he allocated me the house, he kept pestering me and even threatened me, saying that I could never leave him for the rest of my life and that I would have to stay with him even after we got married."

"Unless...unless he's dead." Liao Jiangqun said this and walked out.

Tian Rui said, "How could this happen?"

Ji Jie said, "I expected this to happen. That day when we went to find her fiancé Dong Yinglu, I knew this would be the outcome when Dong Yinglu chased after us." After saying that, she handed the key to Tian Rui and said, "This is the key to her safe. You and Zhang Yang go get the evidence."

"Yes."

Zhang Yang and Tian Rui went to the bank's safe deposit box and took out the contents: a dress, a floppy disk, and a certificate of honor.

Tian Rui opened a certificate and said, "Liao Jiangqun won the sprint championship at the Provincial University Games."

"Good heavens, no wonder she was able to complete the crime in three and a half minutes."

Zhang Yang then took out a dress and said, "This dress should be the one she wore that day." He then searched through it and pulled out a floppy disk. Zhang Yang said, "This should be the elevator operation program she programmed herself. This thing needs to be saved."

Back at the station, in the interrogation room.

Liao Jiangqun sat relaxed in the iron chair, as if chatting casually in her own living room. She recounted the entire crime, sentence by sentence: how she discovered the elevator system vulnerability, how she used Dong Yinglu's laptop to connect to the community's local area network in the 12th-floor telecommunications room, how she logged into the property management computer's backend (the password was admin123, which she said she only tried once and almost laughed out loud). She explained how she set a timer to unlock the door on the 13th floor, how she arranged to meet Tong Jiaxian on the 13th floor, and how she pushed him off the building when he turned around. She spoke the whole story at a leisurely pace, as if she were talking about someone else's business.

After she finished speaking, she leaned back in her chair, looked at Ji Jie opposite her, and even had a faint smile on her lips: "Is there anything else you want to ask?"

Ji Jie put down her pen, looked at her, and asked the most crucial question in the entire case, her tone not harsh: "One last question. Have you considered what would have happened if other people had pressed the elevator button after midnight that night?"

Liao Jiangqun smiled. There was no smugness or mockery in that smile, only a certain confidence in her skills. She said, "There won't be any consequences. I arranged to meet him on the thirteenth floor because no one lives there; all three apartments are empty. It's impossible for anyone to go to that floor late at night. Besides, I've program-locked all the elevator doors on floors other than the thirteenth floor. It's a perfect program."

Zhang Yang had been silent the whole time. When he heard the word "perfect," his lips twitched, but not in a smile. It was the kind of helplessness one feels when a fellow professional looks at an outsider. He turned his laptop around, and several windows were half-open on the screen: the property management computer's system logs, his script analysis report, and the source code of Liao Jiangqun's timer program. Zhang Yang had decompiled the code from the backend logs. The code was only a few dozen lines long, and the logic was very straightforward.

"Liao Jiangqun, Liao Jiangqun," Zhang Yang leaned back in his chair, his tone tinged with amusement and exasperation, "You have too much faith in your program. You say it's perfect, then let me ask you, why haven't you deleted your web logs?"

Liao Jiangqun's expression didn't change, but his gaze shifted slightly in his direction.

Zhang Yang continued, "When you connect your laptop to the community's local area network, the switch records your MAC address and access port. You deleted the scheduled tasks on the property management computer and thought everything was fine, right? But you didn't touch the switch's logs at all. The login time, source IP, and MAC address are all there. That's the first point."

He raised his second finger: "Secondly, you didn't touch the backend management logs of the elevator control host you hacked into. Every operation you performed after logging in—when you checked the elevator status, when you set the timer parameters, when you deleted tasks—the system remembers it all clearly. You only deleted the instruction in the front-end task list; the backend logs remained completely untouched."

Zhang Yang closed his laptop, looked at her, and spoke calmly but with every word hitting the nail on the head: "The program you designed, to put it bluntly, is just adding a few instructions for opening and closing the outer doors to someone else's existing control system, plus a small script that automatically deletes tasks at a certain time. It works, it definitely works, and your idea of ​​locking the elevator's outer doors is quite clever, but your automatic deletion program only deletes running tasks, not logs, doesn't leave any backdoors, and can't even do basic cleanup." He paused, then concluded, "To put it bluntly, your skill level is mediocre at best, you're nothing special."

Liao Jiangqun stared at him for a long while. The interrogation room was quiet for a few seconds, then she looked away, and the confident expression on her face gradually faded.

Liao Jiangqun smiled indifferently and said, "Officer, you're right. Maybe that procedure is a half-baked work in your eyes, but for me, it can free me."

"I don't think you can search me based on mere suspicion, right?"

Ji Jie said, "It seems you have a thorough understanding of the law."

Liao Jiangqun said, "Everything in this world has rules and patterns, but love is the only thing that has no rules, no patterns, too many variables, and is unpredictable."

Ji Jie stood up, picked up the pen, and said to Tian Rui, "Take her away."