Delphi For Fun Newsletter #25



Tuesday  March 12, 2002
Spring is coming!  
We have had several days of temperatures in the mid 50's here on the mountain  last week, after a couple of single digit nights two weeks ago.  So maybe winter will come to an end after all.   
We passed  15,000 home page visitors today!
Soap-box time:   I've been puzzled by the Microsoft bashing in the technical press since the anti-trust trial started.  In the past year I've unsubscribed from most of my email technology newsletters when an issue arrived that was too biased to tolerate.  I recently ran across this Op-Ed piece, Drop the AntiTrust Suit Against Microsoft,  that's a little extreme, but still makes some sense to me.    If you're interested,  read it and decide for yourself.  
I had a birthday last week and received a Mensa puzzle book from a daughter.    So -- expect a couple of problem solving programs based on those puzzles this month.   Also a cool card trick program plus I'm going to figure how to download and interpret the data from that GPS  navigation device I received for Christmas.  That should keep me occupied for a few days.  
In the meantime, here are the "What's New"  details for the last six weeks:

January 30, 2002:  Here's puzzle/game I call Traffic Jam.  It's modeled after the original plastic version,  RushHour,  by Binary Arts.    The objective is to free the target car by moving those that are blocking it's way.   Vehicles can move only in the direction of their long axis.  A simple case with the objective of moving the red car to the exit looks like this: 

Too easy? Try this one

February 10, 2002:  I've been playing with Doodler 2 for several days.  (Doodler 1 was posted about a month ago.)   Printing and rotating drawings is working fine, but kaleidoscope drawing is driving me crazy!

I decided to take a break and work on a few simpler programs.  One is an arithmetic drill program modeled after Arithmattack, a Javascript program  posted at the Argonne National Laboratory website.   My beta tester (aka wife)  complained about my  use of * and / for multiply and divide.   That led to today's posting - a FontViewer written to find those elusive  and symbols.  It could also be useful if you need the , , , or  symbols which are buried in most fonts.   I used the OnDrawCell event exit to display fonts in a Stringrid, so decided to post it over in Delphi-Techniques as an example of this  Stringgrid drawing technique.  

February 13, 2002: Here's the Arithmattack! drill program I mentioned  the other day.   It's a timed drill to see how many basic arithmetic problems can be solved in 60 seconds with user control of the range of values and the operations.   My first thought was that the timing aspect wasn't  good, but I've changed my mind.   We all need to  learn to think under pressure, and this is low-pressure pressure.   Problems can be very simple to start and should build confidence.  See what you think.  



February 15,2002:  What would the Olympics be without rings?  Here's an Olympic Rings puzzle that challenges you to place  one of the digits 1-9 in each of the areas formed by the overlapping rings so that the sum of the digits in each ring is the same.   This is mainly a programming exercise, but you can print a copy of the rings if you want to exercise your brain (and delay Alzheimer's).

February 21: 2002:  From an old ACM Programming Contest, here's a problem I call Slimps, Slumps and Slurpies.   These are strings of characters following certain formation rules. The definitions are recursive, meaning that the rules may include the terms being defined.  The idea is to write a program that recognizes each type.  Kind of a compiler for the "Slurp" language


March 1, 2002:  I ran across this entry the other day in my "Unanswered questions" file:  "Championship golf courses always contain 18 holes with par scores of 3, 4, and 5 with a total course par of 72.   How many possible championship course arrangements are there?"   Here's a 40 line Delphi "GolfCourses"  program that answers the question.   It involves our old friends Permutation and Combination.  If you want to be a good puzzle solver and don't know them,  it may be time to get acquainted.   

Not that it matters,  but I haven't been able to find a definition of "championship golf course" to verify that the premise of the question is true.   

March 7, 2002:  Doodler 2, a drawing program with fill, rotate-draw, and kaleidoscope draw features is available!  And you can now also save and print the masterpieces you create.



"Nothing can stop the man with the right mental attitude from achieving his goal; nothing on earth can help the man with the wrong mental attitude." -- Thomas Jefferson
Or more concisely:
"Whether you think you can or think you can't,  you're right." - Henry Ford

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