CS 100: Lecture L2

January 28

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Template for problems with no graphics:

Obtained by editting the file CUCSApplication.java file that is generated when a project is created using CU CS Application stationary.

// Place high-level comments here

import java.io.*;

public class MyClassName
{	
	public static void main(String args[])
	{
        TokenReader in = new TokenReader(System.in);
	   
	   // My contributions begin here...
		
		

	   // and end here.
	   in.waitUntilEnter();
	}

}

Example L2A: Surface Area Increase

// L2A
// Example L2A: Surface Area Increase

import java.io.*;

public class L2A {
   
   public static void main( String args[]){

      TokenReader in = new TokenReader(System.in);
      
      final double R = 3950.0;   // Earth radius (miles).
      double pavingThickness;    // Paving thickness (inches)
      double deltaR;             // Paving thickness (miles)
      double increase;           // Surface area increase (square miles).
      
      System.out.println("\nEnter paving thickness (inches): "); 
      pavingThickness = in.readDouble();
      
      deltaR = pavingThickness/(12.0*5280.0);
      increase = 4.0*Math.PI*(2.0*R+deltaR)*deltaR;  
      System.out.println("Surface area increase = " + increase + " square miles");
      Format.println(System.out,"Surface area increase = %10.4e  square miles",increase); 
      
      in.waitUntilEnter();
   }
}

 

Template  for problems with graphics:

Obtained by editting the file CUCSGraphicsApplication.java file that is generated when a project is created using CU CS Graphics Application stationary.

// High-level comments here	


import java.io.*;
import java.awt.*;

public class CUCSDrawing extends Frame
{
    // Place constants here
    
    public void paint(Graphics g)
    {
	// Your contributions start here.
	
	

	// And end here.	
    }	
}

public class MyClassName
{
    public static void main(String args[])
    {
       CUCSDrawing d = new CUCSDrawing();
       d.resize(200,150);                     // Modify as appropriate.
       d.move(0,75);
       d.setTitle("Drawing");                 // Modify as appropriate.
       d.show();
       d.toFront();
    }
}

Example L2B: A Sliced Pizza

// Example L2B: Draw a pizza with 8 slices.

import java.io.*;
import java.awt.*;

public class CUCSDrawing extends Frame
{
   final int xc = 450;
   final int yc = 350;   // The circle has center (xc,yc).
   final int r  = 300;   // The circle has radius r.
	
   public void paint(Graphics g)
   {
      // -------------------------------
      g.drawOval(xc-r,yc-r,2*r,2*r);    // Draw the circle.
      g.drawLine(xc-r,yc,xc+r,yc);      // Draw the horizonal diameter.
      g.drawLine(xc,yc-r,xc,yc+r);      // Draw the vertical diameter.
      int d;                            // Declare the "displacement factor".
      d = (int) (r/Math.sqrt(2.0));    
	    
      // The 45-degree points have coordinates (in counter-clockwise order)
	  
      //          (xc+d,yc-d), (xc-d,yc-d), (xc-d,yc+d), (xc+d,yc+d)
	    
	    
      g.drawLine(xc+d,yc-d,xc-d,yc+d); // Connect the first with the third.    
      g.drawLine(xc-d,yc-d,xc+d,yc+d); // Connect the second with the fourth. 	
       

      // --------------------------------------
    }	
}

public class L2B
{
   public static void main(String args[])
   {
       CUCSDrawing d = new CUCSDrawing();
       d.resize(1000,800);
       d.move(0,75);
       d.setTitle("S1_4");
       d.show();
       d.toFront();
   }
}