Exercício do livro java como programar 4ª edição

// Fig. 2.20: Comparison.java
// Compare integers using if structures, relational operators 
// and equality operators.

// Java extension packages
import javax.swing.JOptionPane;

public class Comparison {

   // main method begins execution of Java application
   public static void main( String args[] )
   {
      String firstNumber;   // first string entered by user
      String secondNumber;  // second string entered by user
      String result;        // a string containing the output
      int number1;          // first number to compare
      int number2;          // second number to compare

      // read first number from user as a String
      firstNumber =
         JOptionPane.showInputDialog( "Enter first integer:" );

      // read second number from user as a String
      secondNumber =
         JOptionPane.showInputDialog( "Enter second integer:" );
      
      // convert numbers from type String to type int
      number1 = Integer.parseInt( firstNumber );
      number2 = Integer.parseInt( secondNumber );

      // initialize result to empty String
      result = "";

      if ( number1 == number2 )
         result = number1 + " == " + number2;

      if ( number1 != number2 )
         result = number1 + " != " + number2;

      if ( number1 < number2 )
         result = result + "\n" + number1 + " < " + number2;

      if ( number1 > number2 )
         result = result + "\n" + number1 + " > " + number2;

      if ( number1 <= number2 )
         result = result + "\n" + number1 + " <= " + number2;

      if ( number1 >= number2 )
         result = result + "\n" + number1 + " >= " + number2;

      // Display results
      JOptionPane.showMessageDialog(
         null, result, "Comparison Results",
         JOptionPane.INFORMATION_MESSAGE );

      System.exit( 0 );  // terminate application

   }  // end method main

}  // end class Comparison


/**************************************************************************
 * (C) Copyright 2002 by Deitel & Associates, Inc. and Prentice Hall.     *
 * All Rights Reserved.                                                   *
 *                                                                        *
 * DISCLAIMER: The authors and publisher of this book have used their     *
 * best efforts in preparing the book. These efforts include the          *
 * development, research, and testing of the theories and programs        *
 * to determine their effectiveness. The authors and publisher make       *
 * no warranty of any kind, expressed or implied, with regard to these    *
 * programs or to the documentation contained in these books. The authors *
 * and publisher shall not be liable in any event for incidental or       *
 * consequential damages in connection with, or arising out of, the       *
 * furnishing, performance, or use of these programs.                     *
 *************************************************************************/

package A1;
import java.util.Scanner;



public class exerc3 {
	
	public static void main(String args[]){
		int a,b,c, maior, menor;
		float soma, media, prod;
		
		
		Scanner input = new Scanner( System.in );
		
		System.out.print("Digite o numero 1");
		a = input.nextInt();
		System.out.print("Digite o numero 2");
		b = input.nextInt();
		System.out.print("Digite o numero 3");
		c = input.nextInt();
		soma=a+b+c;
		media=(a+b+c)/3;
		prod=a*b*c;
		
		if (a>c);
		if (a>b);
		{
		
		{
			
			maior=a;
			
			if (b<c);
			{
				menor=b;
				
			}
			
			if (c><b)
				
			{
				
				menor=c;
			}
			
			
		}
		
		}
		if (b>a);
		
		if (b>c)
		
		{
		
		{
			
			maior=b;
			
			if (a<c);
			{
				menor=a;
				
			}
			
			if (c><a);
				
			{
				
				menor=c;
			}
		}
			
			
		}
		if (c>a);
		if (c>b){
		
		{
			
			maior=c;
			
			if (b<a);
			{
				menor=b;
				
			}
			
			if (a><b)
				
			{
				
				menor=a;
			}
			
		}
			
			
		}
		
		System.out.print("a soma é: ");
		System.out.print(soma);
		System.out.print("a media é: ");
		System.out.print(media);
		System.out.print("o produto é: ");
		System.out.print(prod);
		
		
		
		
		
		
	}



}

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