Pour over this

[bonanova]

You have two 10-liter beakers filled with water, and two empty beakers, of capacity 4 and 5 liters, respectively. You may pour from one beaker to another, in such a way that either the source beaker is emptied, or the receiving beaker is filled. The object is for the two smaller beakers each to contain 2 liters of water. No water is to be wasted, and no more than nine pourings is allowed.

[k-man]

Oops, you're right. I skipped a pour.

 

Initial State: 10 10 0 0

1: 10 6 0 4

2: 10 6 4 0

3: 10 2 4 4

4: 10 2 5 3

5: 10 7 0 3

6: 10 7 3 0

7: 6 7 3 4

8: 6 7 5 2

9: 6 10 2 2

[Barcallica]

10-10-5-4 ---> beakers

10-10-0-0 ---> initial state

10-5-5-0

10-5-1-4

10-9-1-0

6-9-5-0

2-9-5-4

7-9-0-4

7-4-5-4

10-4-2-4

10-8-2-0

6-8-2-4

6-10-2-2 ---->finish 11 moves

[bonanova]

Barcallica - nice work.

 

OK we have a solution for 11 pourings.

Can anyone get it down to 10?

Or 9?

[k-man]

Initial State: 10 10 0 0

1: 10 6 0 4

2: 10 2 4 4

3: 10 2 5 3

4: 10 7 0 3

5: 10 7 3 0

6:  6 7 3 4

7:  6 7 5 2

8:  6 10 2 2

[bonanova]

I think your second pour is not right.

[bonanova]

Bravo. Not an easy solve. 

Yes, that is the coveted bonanova gold star.