Beginner Java Exercise: Grouping arguments to avoid confusion

What is a leap year?

"A year, occurring once every four years, that has 366 days including February 29 as an intercalary day."

A year is a leap year if it's divisible by 4 but not by 100, or if it's divisible by 400.

In the above example, we need to group the first 2 arguments together and separate out the third.

((year % 4 == 0 && year % 100 != 0) || year % 400 == 0);

The modulo symbol % is used to find out the remainder once an equation has been evaluated.
i.e. 4 % 2 = 0 | 5 % 2 = 1 | 6 % 2 = 0 | 7 % 5 = 2 since 5 x 1 = 5 r 2

We group the first two statements and then separate the third with the use of parentheses followed by the OR operator ||

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