Java - Check if input is a positive integer, negative integer, natural number and so on.
If you really have to avoid operators then use Math.signum()
Returns the signum function of the argument; zero if the argument is zero, 1.0 if the argument is greater than zero, -1.0 if the argument is less than zero.
EDIT : As per the comments, this works for only double and float values. For integer values you can use the method:
Integer.signum(int i)
What about using the following:
int number = input.nextInt();
if (number < 0) {
// negative
} else {
// it's a positive
}
(You should you as Else-If
statement to check the for the three different state (positive, negative, 0)
Here is a simple example (excludes the possibility of non-integer values)
import java.util.Scanner;
public class Compare {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.print("Enter a number: ");
int number = input.nextInt();
if( number == 0)
{ System.out.println("Number is equal to zero"); }
else if (number > 0)
{ System.out.println("Number is positive"); }
else
{ System.out.println("Number is negative"); }
}
}