Problem 2397. Leap Year

According to Gregorian Calender(which is in use now, in many countries),decide whether a given year is a leap year or not. Give 'true' if the given year is a leap year and 'false',if not.

Note: In the Gregorian calendar 3 criteria must be taken into account to identify leap years:

The year is evenly divisible by 4; If the year can be evenly divided by 100, it is NOT a leap year, unless; The year is also evenly divisible by 400. Then it is a leap year.