Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Example parse tree. An optimal parse tree T for y = bbccd where x = abcd. The root production duplicates x2,4 = bcd. x2 generates y1 and x3 generates y4. The trees T1 and T2 are indicated. T1 is an optimal parse tree for y2,4-1 = bc. T2 is an optimal parse tree for y4,|y| = cd.
