Happy Running, an application for runners, is very popular in CHD. In order to lose weight, fdf decides to run k meters per day with Happy Running. Let’s regard the school as a circular runway with total length of x meters, and fdf could start runningclockwise at a random point on the runway. Then Happy Running will randomly show two punching-card points (打卡点). Because of the poor physical strength, fdf decides to nish running only by completing the punch, whether or not complete the goal of k meters. One day, before running, fdf wants to know whether he can achieve the goal today, and he asks you to help him to calculate the probability of completing the goal running k meters. Note that, fdf should punch card one by one which means that he will punch card at the rst point before the second, even if he reaches the second point rst. It is guaranteed that punching-card points and the point fdf starts running will appears randomly with equal probability and the three points won’t be coincide.
Happy Running, an application for runners, is very popular in CHD. In order to lose weight, fdf decides to run k meters per day with Happy Running. Let’s regard the school as a circular runway with total length of x meters, and fdf could start running clockwise at a random point on the runway. Then Happy Running will randomly show two punching-card points (打卡点). Because of the poor physical strength, fdf decides to finish running only by completing the punch, whether or not complete the goal of k meters. One day, before running, fdf wants to know whether he can achieve the goal today, and he asks you to help him to calculate the probability of completing the goal running k meters. Note that, fdf should punch card one by one which means that he will punch card at the first point before the second, even if he reaches the second point first. It is guaranteed that punching-card points and the point fdf starts running will appears randomly with equal probability and the three points won’t be coincide.
