偶然在一本笑话书上看到一个笑话,说一个数学教师给学生出了这样一道数学题:现有18个人要过河,每条船每次只能坐2个人,问需要几次所有的人才能全部过河?学生:17次。老师:不对,是9次。学生:那么老师船到了对岸谁把船划回来呀?故事到这里就没有了,因为这只是一个笑话,但是我却从这个笑话中发 Occasionally, I saw a joke on a joke book, saying that a math teacher gave students a math problem: the existing 18 people had to cross the river and each boat could only sit 2 people at a time and asked how many times People can all cross the river? Student: 17 times. Teacher: No, it’s 9 times. Student: Then the teacher’s ship to the other side of the ship back to planted it? The story will not be here, because this is just a joke, but I made from this joke