Java Program to Find Largest of Three Numbers

This article is created to cover multiple programs in Java that find and prints the largest of three numbers, entered by user at run-time of the program. Here are the list of programs covered by this article:

• Find largest of three numbers using if ... else
• Find largest of three numbers using nested if ... else
• Find largest of three numbers using conditional operator (?:)

Find Largest of Three Numbers using if else

The question is, write a Java program to find the largest of three given numbers. The program given below is its answer:

import java.util.Scanner;

public class fresherearth
{
   public static void main(String[] args)
   {
      int a, b, c, large;
      Scanner scan = new Scanner(System.in);
      
      System.out.print("Enter the First Number: ");
      a = scan.nextInt();
      System.out.print("Enter the Second Number: ");
      b = scan.nextInt();
      System.out.print("Enter the Third Number: ");
      c = scan.nextInt();
      
      if(a>b && a>c)
         large = a;
      else if(b>a && b>c)
         large = b;
      else
         large = c;
      
      System.out.println("\nLargest = " +large);
   }
}

The snapshot given below shows the sample run of above program, with user input 1, 2, and 3 as first, second, and third number to find and print the largest among these three numbers:

Here is another sample run with user input 1, 3, and 2 as three numbers:

Find Largest of Three Numbers using Nested if else

This program is created by implementing the actual logic behind finding the largest number among three given numbers, using nested if...else

import java.util.Scanner;

public class fresherearth
{
   public static void main(String[] args)
   {
      int a, b, c, large;
      Scanner scan = new Scanner(System.in);
      
      System.out.print("Enter Three Numbers: ");
      a = scan.nextInt();
      b = scan.nextInt();
      c = scan.nextInt();
      
      if(a>b)
      {
         if(b>c)
            large = a;
         else
         {
            if(c>a)
               large = c;
            else
               large = a;
         }
      }
      else
      {
         if(b>c)
            large = b;
         else
            large = c;
      }
      
      System.out.println("\nLargest = " +large);
   }
}

Here is its sample run with user input 20, 10, and 30 as three numbers:

Find Largest of Three Numbers using Conditional Operator

This is the last program of this article, created using conditional operator or ternary operator, that is ?:. I've used the previous program, to wrap the if...else into conditional operator:

import java.util.Scanner;

public class fresherearth
{
   public static void main(String[] args)
   {
      Scanner scan = new Scanner(System.in);
      
      System.out.print("Enter Three Numbers: ");
      int a = scan.nextInt();
      int b = scan.nextInt();
      int c = scan.nextInt();
      
      
      int large = (a>b) ? ((b>c)?a:(c>a)?c:a) : (b>c)?b:c;
      
      System.out.println("\nLargest = " +large);
   }
}

In the following statement, from above program:

int large = (a>b) ? ((b>c)?a:(c>a)?c:a) : (b>c)?b:c;

First the code (condition) a>b gets evaluated. If this code evaluates to be True, then the following code:

((b>c)?a:(c>a)?c:a)

will get evaluated, otherwise the following code:

(b>c)?b:c

will get evaluated. Let's suppose the condition a>b evaluates to be True. Therefore, the following code:

((b>c)?a:(c>a)?c:a)

will get evaluated in a way that the condition b>c gets evaluated. If this condition evaluates to be True, then

a

gets evaluated, otherwise:

(c>a)?c:a)

gets evaluated. This process continues until the whole expression lefts a single variable i.e., a, b, or c. Let's demonstrates the statement using the example given below.

How the Largest of Three Numbers gets Calculated using Conditional Operator

For example, if a=20, b=10, and c=30. Then the statement:

int large = (a>b) ? ((b>c)?a:(c>a)?c:a) : (b>c)?b:c;

gets evaluated as, first the code a>b or 20>10 evaluates to be True, therefore the code ((b>c)?a:(c>a)?c:a) gets evaluated.

That is, the code (b>c) or (10>30) evaluates to be False, therefore the code (c>a)?c:a gets evaluated.

That is, the code c>a or 30>20 evaluates to be True, therefore the code c gets evaluated. That is, no more code to execute, as the final variable is c, therefore the value of c, that is 30 will get initialized to large. That's it.

Same Program in Other Languages

• C Find Largest of three Numbers
• C++ Find Largest of three Numbers
• Python Find Largest of three Numbers

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