Leap year in java

Question

Why doesn't this code work. I am an amateur, started learning java today.

link to java visualiser: http://www.cs.princeton.edu/~cos126/java_visualize/#

this is the code:

public class ClassNameHere {
public static int max(int[] m) {
if ((m % 400 == 0) && (m % 4 == 0) && (m % 100 != 0)) {
System.out.println(m + "is a leap year");
} else {
System.out.println(m + "is not a leap year");

}
}
}
max(2000);

please add the code, say what you expect, and say what you got. — Meier, May 21 '16 at 12:17
Your logic is messed up. If `m % 400 == 0`, then `m % 100 == 0`. — Turing85, May 21 '16 at 12:18
You might want to know this: https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=what%20is%20a%20leap%20year — Tilak Madichetti, May 21 '16 at 12:35

ΦXocę 웃 Пepeúpa ツ · Answer 1 · 2016-05-22T11:01:24.043

1st thing i would say is that the way you operate with objects is not making much sense... And all begin here:

public static int max(int[] m) {
if ((m % 400 == 0) && (m % 4 == 0) && (m % 100 != 0)) {

Since m is an array of ints, there is no logical way for the compiler to understand what would be divide an array by 4 or take the modulo of that division.... that segment of code is not even posible to be compiled.

2nd. this logic here is not correct:

if ((m % 400 == 0) && (m % 4 == 0) && (m % 100 != 0)) {

it must be

if ((m % 400 == 0) || (m % 4 == 0) && (m % 100 != 0)) {

Example:

public boolean isLeap(final int year) {
    return ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0);
}

Gaurav Mahindra · Answer 2 · 2016-05-21T12:33:44.570

Your logic in line if ((m % 400 == 0) && (m % 4 == 0) && (m % 100 != 0))is incorrect. Here is a correct program to check leap year:-

public class DetermineLeapYearExample {
     public static void main(String[] args) {

                    //year we want to check
                    int year = 2004;

                    //if year is divisible by 4, it is a leap year

                    if((year % 400 == 0) || ((year % 4 == 0) && (year % 100 != 0)))
                            System.out.println("Year " + year + " is a leap year");
                    else
                            System.out.println("Year " + year + " is not a leap year");
            }
    }
     Hope it will help

score 0 · Answer 3 · answered May 21 '16 at 12:34

0

max method parameter is an array defined as "int[] m" so max(2000) wouldn't work. Besides that, as stated in other answer, you dont have the main function.

answered May 21 '16 at 12:34

Nooblhu

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Leap year in java

3 Answers3

Example: