You have a ten liter jug, and an eight liter jug. Obtain exactly one liter of water in either jug. You have only 18 liters of water.
1. Fill the 8 liter jug completely with water.
2. Pour the water from the 8 liter jug into the 10 liter jug.
3. Fill the 8 liter jug again.
4. Pour the water from the 8 liter jug into the 10 liter jug until the 10 liter jug is full (2 liters will be left in the 8 liter jug).
5. Empty the 10 liter jug.
6. Pour the 2 liters of water from the 8 liter jug into the 10 liter jug.
7. Fill the 8 liter jug for the third time.
8. Pour the water from the 8 liter jug into the 10 liter jug until the 10 liter jug is full (1 liter will be left in the 8 liter jug).
Now you have exactly 1 liter of water in the 10 liter jug.