💧 倒水谜题Water Jug Puzzle
在线倒水谜题：只用几个没有刻度的水壶，通过装满、倒空和互相倒水，量出正好的升数，比如用 3 升和 5 升的壶量出 4 升。共 12 关，后面的关卡没有水龙头，只能在壶之间来回倒。每关都标出了理论最少步数，步数越接近越能拿满三颗星，可撤销、重来。Water Jug Puzzle online: with a few unmarked jugs, fill, empty and pour between them to measure an exact amount — say 4 L using a 3 L and a 5 L jug. Twelve levels, some with no tap where you can only pour between jugs. Each level shows the fewest possible moves; get close to earn three stars. Undo and restart any time.
点一个壶选中它，再点另一个壶就把水倒过去；选中后也可以按“装满”或“倒空”。Tap a jug to select it, then tap another jug to pour into it; with a jug selected you can also Fill or Empty it.
玩法说明与常见问题How to play & FAQ
「倒水谜题」怎么玩？How do I play Water Jug Puzzle?
每个壶只知道总容量，没有刻度。可以做的操作：装满（从水龙头把壶灌满）、倒空（把壶里的水全部倒掉）、倒水（把一个壶的水倒进另一个壶，直到前一个倒空或后一个装满为止）。只要任意一个壶里正好是目标升数就过关。部分关卡没有水龙头，只能利用已有的水互相倒。Each jug only has its capacity — no markings. You can Fill a jug from the tap, Empty it, or Pour one jug into another until the first is empty or the second is full. You win as soon as any jug holds exactly the target amount. Some levels have no tap, so you can only pour the water you already have between jugs.
为什么 6 升和 9 升的壶能量出 3 升？Why can 6 L and 9 L jugs make 3 L?
把 9 升的壶装满，再倒进 6 升的壶，9 升的壶里就剩 3 升。一般来说，能量出的数都是两个容量最大公约数的倍数。Fill the 9 L jug and pour it into the 6 L jug: 3 L stay behind. In general you can only measure multiples of the greatest common divisor of the capacities.
“最少步数”是怎么算的？How is the fewest number of moves found?
程序在你的浏览器里用广度优先搜索把所有可能的倒法都试了一遍，找出最短的那一种。Your browser runs a breadth-first search over every possible sequence of pours and finds the shortest one.
「倒水谜题」免费吗？需要下载吗？Is Water Jug Puzzle 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.