Very basic GObject/GOval For-Loop

I am currently taking my an AP Java Coding class and I am running into an intersting problem.

I am trying to create 100 random circles with various radii, and random colors in a graphics window using GObjects/GOval. I have tried to isolate the problem and I am certain that something with the communication between the for-loop and the GOval (circle) creation. I also have tried to redo this code several times from scratch but I keep running into the same problem. Specifically my problem is that my graphics windows only displaying one random circle and not 100. Please, please help. My code is below:

Please note that I chose the variable c to dictate the color randomly. There is no rhyme or reason, I just needed a random value to be used.

import java.awt.Color;
import acm.graphics.GOval;
import acm.program.GraphicsProgram;
import acm.util.RandomGenerator;

public class _100_Random_Circles extends GraphicsProgram 
{

    public _100_Random_Circles()
    {
      // Random Number Generator

      RandomGenerator rgen = new RandomGenerator();

      // Random X-coordinate.
      int x = rgen.nextInt(1, 500);
      // Random Y-coordinate.
      int y = rgen.nextInt(1, 500);
      // Random Circle width
      int c = rgen.nextInt(1, 100);
      // Random Circle height
      int d = rgen.nextInt(1, 100);

            for(int i = 0; i < 100; i++)
            {
            GOval circle = new GOval (x, y, c, d);
            add(circle);

            //Color the circles randomly

            if(c <= 10)
            {
            circle.setFilled(true);
            circle.setColor(Color.BLUE);
            }
            else if(c <= 20)
            {
            circle.setFilled(true);
            circle.setColor(Color.RED);
            }
            else if(c <= 30)
            {
            circle.setFilled(true);
            circle.setColor(Color.YELLOW);
            }
            else if(c <= 40)
            {
            circle.setFilled(true);
            circle.setColor(Color.GREEN);
            }
            else if(c <= 50)
            {
            circle.setFilled(true);
            circle.setColor(Color.ORANGE);
            }
            else if(c <= 60)
            {
            circle.setFilled(true);
            circle.setColor(Color.BLACK);
            }
            else if(c <= 70)
            {
            circle.setFilled(true);
            circle.setColor(Color.GRAY);
            }

            else if(c <= 80)
            {
            circle.setFilled(true);
            circle.setColor(Color.PINK);
            }

            else if(c <= 90)
            {
            circle.setFilled(true);
            circle.setColor(Color.MAGENTA);
            }

            else
            {
            circle.setFilled(true);
            circle.setColor(Color.WHITE);
            }
        }
    }
}

As I pointed out first in the comments.

Thats because your xycd definition is outside the loop. Then you have just one value for all circles