Long, long ago, in a corner of the world, there was a country called the country of the blind. The people there have a sad fate - at the age of eighteen, they will gradually lose their eyesight. People living in this country can only rely on young people to remember the route, and repeat the route when they are young and old, so as not to lose their way. However, with the change of age, physical fitness is not static...Children jump close; young people are strong, jump high and far; old people lack strength, jump short. There will eventually be deviations in the path to be taken between the three, so as a teenager, how will you take your steps?