Definition: In this task, you are given a text which is the body of a document. Your job is to classify the topic of the document into these categories: 1)Company, 2)Educational Institution, 3)Artist, 4)Athlete, 5)Office Holder, 6)Mean of transportation, 7)Building, 8)Natural place, 9)Village, 10)Animal, 11)Plant, 12)Album, 13)Film, 14)Written work. Your output should be the category number. Don't generate anything apart from numbers 1-14.
Input: Text:  The St. Louis class light cruisers were a pair of warships that served in the US Navy during World War II. The class was a slight modification of the seven-ship Brooklyn class that immediately preceded them incorporating new higher pressure boilers and a new boiler arrangement with machinery on the unit system: alternating boiler and engine rooms to prevent a ship from being immobilized by a single unlucky hit. Additionally AA armament was improved.

6