Home  |  Introduction  |  Newsletters  |  Programs  |  Feedback

 

 

Search:

Search WWW

Search DelphiForFun.org

Support DFF

 If you benefit from the website,  in terms of knowledge, entertainment value, or something otherwise useful, consider making a donation via PayPal  to help defray the costs.  (No PayPal account necessary to donate via credit card.)  Transaction is secure.

If you shop at Amazon anyway,  consider using this link. 

     

We receive a few cents from each purchase.  Thanks

 

 

The index page for all Programs on the site?

The DFF Play CD?

Zipped file DFF Play CD.zip contains  executable version of about  75 of the 200+ programs from the site, mostly those I particularly liked or thought would be of widest interest for non-programmers.  The file is rather large, about 20mb..

Anything else?

Google
 

 

    

Search WWW

Search DelphiForFun.org

 

Not a programmer (yet)?

 That's OK -  the executable version for any puzzle or  game you find here is available for download.  Just scroll down to the bottom of most any description page and you'll find a "Download executable" link. Downloaded programs are in "zipped" format to reduce size and may require an "unzipper" program unless you are running Win XP or later.  Here's a link to a free one. 

Check  out  the Most Popular  Downloads from DFF   (updated weekly)

First time visitor?

Take a look at the Introduction page to see what this site is about

Notes for Teachers

 

Delphi For Fun Newsletter #53

July 16, 2009

 

The quarterly newsletter is late this time, but I have a few good excuses.  One is just old age -  it simply takes longer to do everything these days J.  Plus, we spent two weeks traveling and attending grandkids high school graduations and the family without a graduate this year visited our place for a week over the 4th of July.   The garden is in full bloom and needs daily tending.  Finally, our newest family member is having a major impact on  programming productivity!   

 In addition to the direct impact shown here, I probably spend an hour per day  animating his “mice” (cat toys, paper balls, tissues, string, bits of plastic wrappers, and anything else that moves when he bats at it).  I’m also spending time  building a “Cat Castle”, a 4x4 post with spiral steps leading up to an elevated platform.  The plans call for an elaborate castle on top, but I’ll defer that until I see that he will actually use it.

 

 

 

 

 

 

Here is a summary of, and links to, the programs posted since our March newsletter.

 

April 4, 2009:  While the design of the bookmark might be perfect, there was room to improve the implementation.  Perfect Bookmark V4 was posted today with a few image and font handling enhancements.

April 6, 2009:  Brute Force is one of my favorite programs on the site.  It can solve a wide range of puzzles/problems which have a restricted range of integer solutions.  Give the program the possible variable values and the equations describing the conditions to be met, and the program does an exhaustive search for sets of values satisfying the conditions.   The download files include 24 sample problems.  Brute Force Version 2.3 posted today allows problems with fewer variable values than variables to be solved.  The newly  included  "Binary Conversion" sample problem finds numbers between 6 and 16 with the two middle digits in the binary representation having the same value.    

April 12, 2009: 

 Concentration is the card game requiring that pairs  of face-down cards be drawn and replaced until a match is made.  In case that game is too easy, Concentration Version 2 adds the option of requiring sets of three matching cards be found before they are removed. 
  

April 22, 2009:  It has been a while since we have had a beginners program posted, so here is one that some might have fun with.  Number Words converts any input integer between 0 and a million to words.  So 456,789 as input  for example, displays the result "Four hundred fifty-six thousand seven hundred eighty-nine".  About 60 lines of user written code do the job.

May 1, 2009:

  A week of algebra, geometry, and trigonometry refreshers was enough to convince me what I was already quite sure of, but had never proven, that parallel rays striking a parabolic surface are indeed all reflected to a common focal point.  Here is a Parabolic Reflections program which applies the math to see where it takes us.    The web page steps through the required math.  

 

May 2, 2009:  I decided last night that Parabolic Reflections posted yesterday should be able to display more information about  the intermediate steps in defining the reflected ray.   Parabolic Reflections Version 3.1  posted today corrects that deficiency.

 

May 7, 2009:   

 The objective of the Forbidden Connections Puzzle is to enter the digits 1 through 6 in the circles in this diagram in such a way that no  number is connected to its adjacent value.  (For example, there can be no line connecting the "3" circle with the "2" circle or the "4" circle, etc.)  The program allows user play, finds the two valid solutions, and gives user hints if needed.   
 
 

May 12, 2009:  A housekeeping update today replaces DFF Library zipped file DFFLibV12 with DFFLibV13.  The library file contains a number of units which are used in multiple programs here on DFF.  Any of modified units methods included here reflect minor bug fixes or have already been included in source code of programs which required the enhancements .  Library units which are currently duplicated in program source code will be removed as those programs are updated, so no need for any immediate action by programmers.   The library zipped file contains text file DFFVLib13.txt describing the changes in this version.    One program, Big IntegersTest, has also been reposted with new buttons to test the five new methods in our large integer class, TInteger, which resides in unit UBigIntsV3.

May 14, 2009: Oops - I changed everything in the DFF Library update except the actual file name in the download code.   I was clued by the fact that  the old version, DFFLibV12, was the downloaded 23 times yesterday.  If you were one, please try it again.      

May 19, 2009:

  Today's puzzle assignment, should you choose to accept it, is to rearrange the numbers 1 through 16  in a 4x4 grid so that the sum of any two adjacent numbers, horizontally or vertically, form a prime number.   (Prime numbers are positive integers divisible only by 1 and themselves.)   No credit given for the sample shown here. J  After you give up, program Prime Pair Sums will show you the other 2991 ways to do it.
 

 

May 27, 2009:  Summer is rapidly approaching and programming time is getting reduced by gardening, lawn mowing, grandchildren graduating (2 more from high school this year).   I decided to post a puzzle from my future projects file that I had written a year or so ago but never got around to document.   The problem is to find all 5 digit numbers that contain the same 5 digits when they are multiplied by 3.   Then,  coincidentally,  yesterday's Mensa Puzzle-A-Day calendar had another puzzle related to the number 3:   Find  all 3 digit numbers, N, which together with 2*N and 3*N contain the digits 1 through 9 exactly once. Today's Treble Puzzles posting solves both of these.
 

June 8, 2009:

http://delphiforfun.org/images/BattleshipLowerGrid.pnghttp://delphiforfun.org/images/BattleshipUpperGrid.png Here is a solitaire version of the classical Battleships game where, in addition to the ship quantities and types, you are supplied with the number of ship parts hidden in each row or column and a few preplaced ship parts.  Battleship Puzzle allows user play for a couple of sample problems which will save a bushel of eraser crumbs over pencil and paper solutions J

 

June 14, 2009;  Here is a "Ones" puzzle solver that finds solutions for two odometer puzzles from recent Car Talk radio programs:

  1. On a six digit odometer registering from 000000 to 999999, how many times will the digit "1" appear in all of the possible numbers?
  2. On the same six digit odometer, how many of the possible values contain no "1"s? 

My version also answers "How many numbers contain exactly 1 occurrence of 1?" and other variations for other odometer lengths up to 8 digits. 

June 16, 2009:  We are off for a week or so to help, or at least congratulate, a third grandchild in his transition from high school to college.  I decided to get one more program posted before the hiatus. 

 SortHTMLByDate  is a utility which will sort a  webpage with dated entries, such as this home page, into ascending date sequence.  Seems like a good idea for arranging entries for archival reading once they are moved to the “What's New Archives” as indexed at the bottom of the DFF home page.   (Only are few have been converted so far as test cases.) 

 


Two views of success.  My truth is somewhere in between:

 

"Talent is cheaper than table salt. What separates the talented individual from the successful one is a lot of hard work. " -- Stephen King  (Author)

 

"A man is a success if he gets up in the morning and goes to bed at night and in between does what he wants to do. " -- Bob Dylan (Musician)

 

 


 

To subscribe or unsubscribe from this newsletter, visit http://delphiforfun.org/newsletter.htm

 

??? home page visitors since Sept 2000. (Hit counter broken!)     297,000 program downloads in the past 12 months!


 
 

 

  [Feedback]   [Newsletters (subscribe/view)] [About me]
Copyright © 2000-2017, Gary Darby    All rights reserved.