Dr. Vladimir I. Levenshtein
Interpretation by Jan @Novoj NovotnÃ½
Compute minimal set of operations to apply on left tree to get to the structure of the right one.
Levenshtein distance is a string metric for measuring the difference between two sequences. Informally, the Levenshtein distance between two words is the minimum number of singlecharacter edits required to change one word into the other. It is named after the Soviet mathematician Vladimir Levenshtein, who considered this distance in 1965.
Allowed operations:

Example:Levenshtein distance here is 3 
A A( B C C( D D( E F )D )C G H )A I I( J )I
Algorithm uses stack of operations instead of plain numbers. Imagine that under the number 3 is following stack of operations:

And finally apply modification recipe applied on source tree.
Conflicts may still occur.
Sources:
Contact me @Novoj or novotnaci@gmail.com