Once upon, there was a famous couple between on earth, just because the girl was a fairy coming from the sky and the boy was just a farmer whose unique property was an old bull. A talented poet had written a poem for them, saying that,” Clouds float like works of art. Stars shoot with grief at heart. Across the Milky Way, the cowherd meets the maid, when autumn’s golden wind embraces dew of jade. All the love scenes on earth, however many fade. Their tender love flows like a stream. This happy date seems but a dream. Can they bear a separate homeward way? If love between both sides can last for age, why need they stay together night and day?”
Even though the boy’s mother-in-law was extremely cruel, she reluctantly allowed her daughter and her son-in-low meeting once in one year along the Milky Way. The boy was perturbed and moved between two locations in a straight line, back and forth at a fixed speed. The girl was eager to see her husband, so she would pick the straightway road which is a line and fly to her sweetheart at a maximal speed. Now they wanted to know whether they could have a date successfully. If their minimal distance was longer than their eyesight distance, they would miss each other, so it’s your job to calculate their minimal distance. Be careful that they started at the same time.