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Decision Making

7. Simulated Program



Answer:
    Enter an integer:
12
The number 12 is zero or positive
Good-bye for now
Only the true-branch was executed because the answer to the question num < 0 was true.







Simulated Program

Here is a simulation of this program (using JavaScript so it runs in your browser). Of course, for maximum benefit copy the program to a file and run it. But, play with the following if you want. Perform the steps 1, 2, and 3 under the simulated monitor as many times as you want. (Note: if this does not work, your browser does not have JavaScript enabled. Skip this and go on to the next page.)

import java.util.Scanner;

public class NumberTester
{
  public static void main (String[] args) 
  {
    Scanner scan = new Scanner( System.in );
    int num;

    System.out.println("Enter an integer:");
    num = scan.nextInt();
    
    if ( num < 0 )                
      System.out.println("The number " +
           num + " is negative"); 
    else
      System.out.println("The number " + 
           num + " is zero or positive"); 
    
    System.out.println("Good-bye for now"); 
  }
}

        Simulated Monitor





2. Click in the "monitor" window after the last line and enter a number

This is just a simulation (using JavaScript), so it is not exactly like a compiling and running a real Java program. Don't take it too seriously. Please do the real thing if you can. Try this on-line compiler: http://ideone.com/ if you don't mind a few ads.




Question 7:
Try the program (or look at the flowchart) with the value 0 (zero). What is the output?