397. Measuring Water. A maid was sent to a spring with two vessels of 7 and 11 pints capacity. She needs to bring back exactly 2 pints of water.

What is the minimum number of operations in this case? By "operation" we mean either filling a vessel, emptying it, or pouring water from one vessel to another.
397. Two pints of water can be measured in 14 operations, if the vessels above the line are empty, and each line corresponds to one operation.

\begin{tabular}{cr}
7 l & 11 l \\
\hline 7 & 0 \\
0 & 7 \\
7 & 7 \\
3 & 11 \\
3 & 0 \\
0 & 3 \\
7 & 3 \\
0 & 10 \\
7 & 10 \\
6 & 11 \\
6 & 0 \\
0 & 6 \\
7 & 6 \\
2 & 11
\end{tabular}

The contents of the vessels, specified after each operation, do not require explanations.