Given Table of Cities , Find Minimum Number of Hopes Required to Fly From One to Other City

There is a very Primitive Database and it has a table say "Travel". The content of table is as follows:

Source | Dest
--------------


Sea | LA
LA | FL
LA | MA
FL | Sea
Sea | FL

The ask is to find out all routes between (Sea) to (FL) with mininum hop.
the Result would be:
1. Sea -> FL
2. Sea -> LA - > FL

You have to write a Middle tier function to achieve above result. You can assume there is DBAPI that return the Destination city if you provide the source city.