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nested for loops to draw rectangles

rbjanaki asked:

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import javax.swing.JFrame;
import java.awt.Color;
import java.awt.Graphics;
public class RedAndBlackSteps extends JFrame
   public int startX, startY;
   public static int brickWidth, brickHeight, brickSpace;
   public static int numberOfRows;
   public RedAndBlackSteps()
      super ("Pyramid");
      startX = 400;
      startY = 50;
      brickWidth = 50;
      brickHeight = 50;
      brickSpace = 2;
      numberOfRows = 5;
public void paint(Graphics g)
   int currentX = startX;
   int currentY = startY;
   for (int i = 0; i < numberOfRows; i++) //for loop used to draw the bricks      building the steps
      for (int j = 0; j <= i; j++)
      g.fillRect(currentX, currentY, brickWidth, brickHeight);
      currentY = currentY + 50 + brickSpace;
      currentX = currentX - 50 + brickSpace;
public static void main(String[] args) // main used to display GUI dialogue box
   RedAndBlackSteps app = new RedAndBlackSteps();
   app.setSize(800, 400);
   app.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //when user presses "X" the    dialogue box will close

I want to draw like this
red block on the top first row
red black red for the second row
red black black black red for the third row etc for 5 rows

until now I am able to draw only red blocks

can anybody please help me
Tags: Java


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