A Snail's Mile

Are you willing to trade one kilometer of escape for 100 million? Lin Shen, a 28-year-old programmer, saw a pop-up multiple-choice question in a rental house late at night. He smiled and clicked "Being chased by a snail and getting 100 million yuan." The money is real. But so do snails. It is immortal, immortal and indestructible. It always knows where he is. It was crawling toward him at a speed visible to the naked eye. Once it touches his body, he will die. The only consolation is - it's slow now...