Java Program to Find Largest of Three Numbers

Problem Description

Write a Java program to find the largest number among three given numbers.

Code

public class LargestNumber {
    public static void main(String[] args) {
        double n1 = -4.5, n2 = 3.9, n3 = 2.5;

        if( n1 >= n2 && n1 >= n3)
            System.out.println(n1 + " is the largest number.");

        else if (n2 >= n1 && n2 >= n3)
            System.out.println(n2 + " is the largest number.");

        else
            System.out.println(n3 + " is the largest number.");
    }
}

Output

3.9 is the largest number.

Explanation

1. if-else if-else Ladder: Checks conditions sequentially.
2. n1 >= n2 && n1 >= n3: Checks if n1 is greater than or equal to both n2 and n3.
3. n2 >= n1 && n2 >= n3: Checks if n2 is greater than or equal to both n1 and n3.
4. If neither is true, n3 must be the largest.

Try Yourself

Test your logic with these challenges.

1. Change Values: Set n1 = 10, n2 = 20, n3 = 30 and run the program.
2. Find Smallest: Modify the conditions to find the smallest of the three numbers.
3. All Equal: What happens if n1 = 5, n2 = 5, n3 = 5? Trace the code.
4. Four Numbers: Can you extend the logic to find the largest of four numbers?
5. Brain Twister: Can you solve this using the ternary operator (? :) in a single line? double largest = (n1 >= n2) ? ((n1 >= n3) ? n1 : n3) : ((n2 >= n3) ? n2 : n3);