Game guide · BJTENGYUE
Water Jug Puzzle: rules and examples
Begin with the basic rule, then follow the result of your action. Measure the target number of litres using two unmarked jugs and only filling, emptying and pouring. Try the rule on the board, then read the next instruction. Choose one of six capacity-and-target puzzles. Both jugs begin empty. Try the rule on the board, then read the next instruction.
Six verified solvable capacity puzzles, with undo and move count. These are six levels of one game, not six separate games.
One thing to notice as you play
The example and rules describe the same game you can play above. A pour stops when the source is empty or the destination is full. It cannot stop at an arbitrary amount.
Understand the aim
Measure the target number of litres using two unmarked jugs and only filling, emptying and pouring. Try the rule on the board, then read the next instruction.
The playing sequence
- Choose one of six capacity-and-target puzzles. Both jugs begin empty.
- Fill a jug to its capacity, empty it completely, or pour from one jug into the other.
- A pour stops when the source is empty or the destination is full. It cannot stop at an arbitrary amount.
- Reach the target quantity in either jug. Undo lets you try another route.
Getting comfortable with the controls
Use Fill A, Fill B, Empty A, Empty B, Pour A → B and Pour B → A. The display shows current and maximum litres. Start a new round when you are ready to try again.
Try this example
A careful first move helps you understand the round. With 3- and 5-litre jugs, fill the 5-litre jug and pour into the 3-litre jug. The 5-litre jug now contains 2 litres.
Keep this in mind
A careful first move helps you understand the round. You cannot measure a partial fill directly. Only the allowed actions can create a quantity. Start a new round when you are ready to try again.
Further help with the game
What is the aim of Water Jug Puzzle?
Measure the target number of litres using two unmarked jugs and only filling, emptying and pouring. The instructions above use these same rules.
How do the controls work?
Use Fill A, Fill B, Empty A, Empty B, Pour A → B and Pour B → A. The display shows current and maximum litres. The instructions above use these same rules.
For this game, can you show an example?
With 3- and 5-litre jugs, fill the 5-litre jug and pour into the 3-litre jug. The 5-litre jug now contains 2 litres. The controls work with mouse or touch.
On this page, which mistake should I avoid?
You cannot measure a partial fill directly. Only the allowed actions can create a quantity. The instructions above use these same rules.
During a round, what rules and limits are used here?
Six verified solvable capacity puzzles, with undo and move count. These are six levels of one game, not six separate games. The game is played locally in your browser.
When I start, how many people can play here?
Solo. This is local browser play, not internet matchmaking. The instructions above use these same rules.
When I start, where must the target volume end up?
In either jug. The other jug may contain any legal amount. The worked example offers another way to follow the rule.
Can I stop a pour halfway?
No. The source must empty or the destination must fill. The instructions above use these same rules.
When I start, why is an action disabled?
It would not change the current jug contents, such as filling a full jug. Keep the current game state in view while applying this rule.
On this page, how many puzzles are included?
Six capacity-and-target combinations are selectable on the board. You can start a new round from the game controls.
