⛵ 农夫过河River Crossing
在线农夫过河：经典的过河逻辑谜题合集。从“农夫、狼、羊、白菜”开始，到“三个商人三个随从”“一家人过河”“两个大人两个小孩”，再到“五个商人五个随从、三人船”，一共 5 关。船坐的人有限、谁会划船有讲究，岸上还有各种“不能单独相处”的规矩，每关都标出了最少趟数，可撤销、重来。River Crossing online: a set of classic crossing puzzles. Start with the farmer, wolf, goat and cabbage, then three merchants and three servants, the family on the river, two adults and two children, and finally five merchants and five servants with a three-seat boat — five levels. The boat is small, only some can row, and some characters can't be left together; each level shows the fewest crossings possible. Undo and restart any time.
点船所在岸边的人或物上船，再点船上的可以下船；带黄点的会划船。Tap someone on the bank where the boat is to board, tap them in the boat to get off; a yellow dot means they can row.
玩法说明与常见问题How to play & FAQ
「农夫过河」怎么玩？How do I play River Crossing?
每关开头所有人和物都在左岸，目标是全部送到右岸。点击船所在岸上的角色让他上船（超载上不去），再点“开船”，船到对岸后乘客自动上岸。船上必须有一个会划船的人。每次开船后都会检查两岸：如果出现规则不允许的组合（比如农夫不在时狼和羊在一起），这一趟就失败，可以撤销重来。每关都会算出理论上的最少趟数，越接近星越多。Everyone starts on the left bank and must reach the right bank. Tap a character on the boat's bank to board (if there is room), then press Go; on arrival passengers step ashore automatically. Someone who can row must be aboard. After every crossing both banks are checked: if a forbidden combination appears — say the wolf with the goat while the farmer is away — that crossing fails and you can undo it. Each level knows the fewest possible crossings; get close for more stars.
农夫过河最少要几趟？What is the fewest number of crossings for the farmer?
7 趟：先带羊过去，空船回来；再带狼（或白菜）过去，把羊带回来；然后带白菜（或狼）过去，空船回来；最后再带羊过去。Seven: take the goat over and come back alone; take the wolf (or cabbage) over and bring the goat back; take the cabbage (or wolf) over and come back alone; finally take the goat over.
“最少趟数”是怎么算的？How is the fewest number of crossings worked out?
程序在你的浏览器里把所有合法的过河方法用广度优先搜索试了一遍，找出最短的那条路。Your browser runs a breadth-first search over every legal sequence of crossings and finds the shortest one.
「农夫过河」免费吗？需要下载吗？Is River Crossing free? Do I need to download anything?
完全免费，无需注册、下载或安装，打开网页就能玩，手机、平板和电脑都支持；游戏完全在你的浏览器本地运行，不会上传任何数据。It is completely free with no sign-up, download or install — just open the page on a phone, tablet or computer. The game runs entirely in your browser and nothing is uploaded.