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The index page for all
Programs on the site?
The DFF Play CD?
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..
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
link to a free one.
Check out the
Most Popular Downloads from
DFF (updated weekly)
First time visitor?
Take a look at the
page to see what this site is about
Notes for Teachers
July 3, 2015
Fun Newsletter #77
In the non-computer arena, we've
enjoyed seeing last year's baby twin deer reappear - the girl with her new
spotted baby and the boy sporting a new pair of 5 inch velvet antlers.
Best of all, Mama (now a Grandma) is back with the next pair of twins bouncing
around the yard. Lots of rain promises a bumper crop of wild blackberries
and tame blueberries this year. We're hoping that there are enough
blackberries for the deer and bear to share with us. One
brave crow had to sacrifice her life to a shotgun in order to save the
blueberries for us humans. Yum-yum (for the berries, not the crow!)
Only eight program postings this
quarter, but they cover the range from simple to advanced complexity, user to
programmer oriented, and "just for fun" puzzles to serious mathematical
April 13, 2015:
Here's an interesting little puzzle that
requires some human thought to solve efficiently:
A farmer tells his son to select five watermelons to take to market. Because
the watermelons are sold by weight, they must be put on a scale before the trip
to town, but the son makes a small mistake and weighs them in
pairs. Here are the weights he comes up with, in pounds:
20, 22, ,23, 24, 25, 26, 27, 28, 30, 31.
How much does each of the watermelons weigh? (Source:
Sit & Solve® Brainteasers (Sit & Solve® Series)
The Weighing Watermelons
program posted today implements the solving strategy.
April 19, 2015:
A buddy of mine is designing a Veteran's Day monument which will consist of
panels representing the Armed Forces services and aligned in such a way that the
sun will cast a shadow on the memorial plaque on November 11 at 11:AM. At
his location, he thought that the sun would cast the shadow again in February
when the the sun will be at the same altitude at that hour. I took
advantage of the opportunity to educate him about the "analemma" figure 8
shape of the sun's path through the sky and assure him that the February sun at
11 AM will be about 10 degrees further East than the November path. I
updated AstroDemo Version 2.0, our
Astronomy unit test program, with an "animated" analemma. That option helped me
determine that at 11:11 AM in Lucedale, MS, the crossing point of the figure 8
occurs on February 12 as days are getting longer and August 29 on the way back
down, so no problem for Jim's project!
April 29, 2015:
Three points are placed randomly on the circumference of a circle. What is the
probability that all three points lie within the same semicircle?
Check out Circular
Reasoning to verify your answer.
May 11, 2015:
A viewer discovered a memory
leak in our Big Integers unit which carried over to the Big Float unit.
UBigIntsV4 allows mathematical operations on integers whose size is only
limited by available memory and UBigFloatV4 extends the extended
precision feature to floating point numbers using UBigIntsForFloatV4 for
the integer parts. The Free method in both of the big
integers unit released the memory specifically allocated by the program but
neglected to call the inherited Free method which releases the memory
taken by the system when the integer object was created.
Today's' postings include a revised library zip file,
DFFLibV4_11May2015 containing the
revised units. Two test programs,
BigFloatTest were modified to report
allocated memory after each operation to verify the correction and to help
indentify future memory release problems.
May 31, 2015:
Just time to squeeze in one more
little program this month. Outdoor activities have taken up most of my
time recently and most of the daily Mensa Calendar puzzles are either solvable
by programs I've already written or are not amenable to being solved by
computer. But yesterday's offering was a good candidate so here it
is: "A surprising number of U.S. state
names contain multiple pairs of letters which form standard two-letter state
abbreviations. For example ALABAMA contains two: AL and MA (Alabama and
Massachusetts). If we don't allow overlapping abbreviations, there is only
one state name that contains as many as four abbreviations. Can you
find it?" Search
State Abbreviations is a 50 line program which finds the answer
by listing and counting the embedded abbreviations for all 50 states. The
preceding link is to a page of twenty or so Beginner's level programs.
Just click the bookmark or scroll to the bottom of that page to download the
source or executable for the new program.
June 10, 2015:
Black clouds - not so good
A program illustrating many graphic
manipulation effects in Delphi was posted 12 years ago. It was largely
written by a young Czech programmer, Ivan Sivak, who I'm sure has moved on to
bigger and better things by now. I made only minor changes to his code
before posting it. A fix was posted today in the Contrast/Brightness
section of Graphic
Effects correcting a problem of white or light gray pixels displaying as
June 17, 2015:
A License Key Generator program was posted
several months ago to explore how unique keys might be generated to allow
a program to verify owner or expiration date information. To my
surprise, the program was recently flagged as a "Keygen Trojan" by a well
respected security scanner. I revisited the source code and made a few
formatting and spelling enhancements and the warning disappeared. So, just
in case, I reposted the
License Key Generator V1.1 program today.
June 29, 2015:
posted today, implements a solver for this Mensa® calendar
puzzle from March 16, 2015. It uses a search technique probably used by
most human solvers; concentrating on the word intersections to find candidates;
the program just does it a lot fasterJ.
"If people knew how hard I had to
work to gain my mastery, it would not seem so wonderful at all." - Michaelangelo
"Talent is cheaper than table salt. What separates the
talented individual from the successful one is a lot of hard work." - Stephen
"History has demonstrated that the most notable
winners usually encountered heartbreaking obstacles before they
triumphed. They won because they refused to become discouraged by their
defeats." - B. C. Forbes (Journalist)
"An inventor fails 999 times and, and if he succeeds
once, he’s victorious. He treats his failures as practice shots."
-Charles F. Kettering (Inventor)
"Hasten slowly, and without losing heart put
your work twenty times upon the anvil." -Boileau (Poet)
"Tyranny like hell, is not easily
conquered yet we have this consolation with us, the harder the conflict,
the more glorious the triumph. What we obtain too cheap, we esteem too
lightly; it is only dearness that gives everything its value.”
Thomas Paine (Patriot)
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