Before graduating from university in 2023, Lin Xing had experienced this kind of time travel three times. Judging from these limited three experiences, he believed that the length of time he traveled back to the past should be related to the size of the danger.,But at this moment, Lin Xing looked at the somewhat familiar university teaching building in front of him, his brain felt like a lump of mud, confused and lost.,It was this idea that led Lin Xing into a thought: "If I call the police many times and the operator doesn't believe what I say, am I wasting police resources"。