isNeighbor(?A, ?B) ^ isNeighbor(?B, ?C) -> isReachable(?A, ?C) |
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.