USER-DEFINED METHODS - Java Programming: From Problem Analysis to Program Design - page 448

Identify and correct errors in the following program:
public class Chapter7Ex9
{

9.

public static void main(String[] args)
{

System.out.println(signum(12));
System.out.println(signum(-11));
System.out.println(signum(20.5));
System.out.println(signum(0));

}

public static int signum( int x)
{

if (x > 0)
return 1;
else if (x == 0)
return 0;

else

return -1;

}

}

Find and correct error(s) in the following method definition:
public static void doubleNum( int x)
{

10.

return 2 * x;

}

Find and correct error(s) in the following method definition:
public static int squareNum( double x)
{

11.

return x * x;

}
12. Consider the following program:
import java.util.*;

public class Chapter7Ex12
{

static Scanner console = new Scanner(System.in);

public static void main(String[] args)
{

double num1;
double num2;

System.out.print("Enter two integers: ");
num1 = console.nextInt();
num2 = console.nextInt();
System.out.println();