What If a Science Student Among Liberal Arts Students Traveled Through Time?

A time travel article. The hero and his roommate traveled through time together The male protagonist traveled through time and inhabited the body of an emperor, but he didn't know where his roommate was, so he sent someone to post a notice on the emperor's door and wrote a poem. The notice said that if he could match the sentence, he would be made prime minister immediately. That poem is: Odd changes to even and remains unchanged. Intention: Work hard to succeed, reach the pinnacle of life