title: Printing an arrowhead of stars using nested for loops
body: <p>Print an arrowhead.
  Let the user input how big the arrow should be by entering the total number of lines to draw.
  The user entered 9 in the example below. Prompt the user to enter an odd number only.
  It should model this:</p>
  
  <pre><code>*
  **
  ***
  ****
  *****
  ****
  ***
  **
  *
  </code></pre>
  
  <p>So far my code looks like this:</p>
  
  <pre><code>    int i, j, numRows;
      Scanner reader=new Scanner(System.in);
  
      System.out.println("How many rows would you like the triangle to have?");
      numRows=reader.nextInt();
      //row
      for(i=1;i&lt;=numRows;i++){
          //column
          for(j=1;j&lt;=i;j++){
              System.out.print("*");
  
          }
          System.out.println();
      }
  }
  </code></pre>
  
  <p>}</p>
  
  <p>this is the top half. i can make the bottom half by altering the nested loop.  I know that I need to  have the nested loop decrease the amount of stars after it reaches the middle column, or (i/2)+1, but I am not sure how to do this.  I tried using an if statement with j-- inside of the column loop but either that is not correct or I made a mistake.</p>