Summer olympics are held on years that are divisible by 4. Winter olympics are held on the other even years. No olympics are held on the odd years.

Summer olympics are held on years that are divisible by 4. Winter olympics are held on the other even years. No olympics are held on the odd years. Given a year, return which olympics will be held that year, either "winter", "summer", or "none".

whichOlympics(2014) → "winter"