试运用深度优先搜索算法寻找过河问题的一个解决方案，题目叙述如下：猎人、狗、男人带着男孩1、男孩2，女人带着女孩1、女孩2，一共8个个体。一艘小船，一次只能过两个个体，狗和四个小孩不会划船。注意：（1）猎人不在，狗咬任何人；（2）男人不在，女人打男孩；（3）女人不在，男人打女孩。-Test the use of depth-first search algorithm to find a solution to cross the river problem, topics are described below: hunters, dogs, a man with a boy a boy, a woman with a girl a girl 2, a total of eight individuals. A boat, once only two individuals, dogs and four children will not be boating. Note: (1) are not hunters, dog bites any person　(2) is not a man, a woman playing a boy　(3) is not a woman, a man playing the girl.