Java Programming

Question

Hi, I'm new to Java. I've been working on this question, wrote the code and checked the results with some examples and it seems to be doing fine. I would be glad if any of the tutors can check the code for me.

Also, please do let me know if there's a more efficient way for writing the code.

Many thanks!

Question :

Write a Java program that replies either Leap Year or Not a Leap Year, when a year is given as keyboard input.

(i) A Year is a Leap Year if the year can be divided by 4 but not by 100

(eg: 1976).

(ii) A year that can be divided by both 4 and 100 is Leap Year if it can also

be divided by 400.

My code :

package exams;

import java.util.*;

public class Exams {

public static void main(String[] args) {

Scanner input = new Scanner(System.in);

int p, q, r, s;

System.out.print("Enter Year");

p = input.nextInt();

if(p%4==0){

if(p%100==0){

if(p%400==0){

System.out.println("Leap Year");

}

}

else if(p%100!=0){

System.out.println("Not a Leap Year");

}

}

}

}

Answer 1

I think you are doing pretty well for a beginner. As for more efficient ways to do things, or more elegant, sure there are. That's the beauty of programming, there is always more than one way to get the desired result. Mostly it would be streamlining the code in this specific example, or snazzing things up with a loop to repeat the leap year check or exit.

From the original problem:

(i) A Year is a Leap Year if the year can be divided by 4 but not by 100

(eg: 1976).

(ii) A year that can be divided by both 4 and 100 is Leap Year if it can also

be divided by 400.

I am wondering what years you tested with, since your nested ifs should be giving only years like 2000 the "Leap Year" thumbs up, and giving a false negative to years like 1960?

I am thinking that using a logical operator in your if statement would work better, and be more efficient.

The pseudo code would look like:

if p can be divided by 4 and not by 100 or p can be divided by 4 and by 100 and by 400

print "Leap Year"

else

print "Not a Leap Year"

the actual code snippet would look like :

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

{

System.out.println("Leap Year");

}

else

{

System.out.println("Not a Leap Year");

}

Since the year either is or isn't a leap year, the second check that you wrote in (after your nested ifs) is not needed.

Good test years would be 1951, 1960, 2000 and 3000, since the first and last are not leap years and the middle two are.

What do you think?

Take a look at (https://www.programiz.com/java-programming/operators) for more on operators.