Three couples are on vacation.They need to cross the river to reach their hotel. There are 3 rules which are as follows :
Rule 1: - The boat can only carry two people at a time. If the third person trying to get in the boat then the boat will sink.
Rule 2: - The husbands are so jealous that they can not let their wife with another man, without their presence.
Rule 3: - The boat cannot run on itself. At least one person should be on the boat to go from one side to another.

How many trips does it take them to all get across the river?
Note: The couples can be identified by their matching color clothes and there is no other way of going to the hotel.

The Answer is an integer . Just put the number without any decimal places.