I’m frustrated, as are many investors, at the lack of interest generated in “savings” accounts these days. It’s pitiful. The interest formula is based on solid mathematics, which is easy to code in C. Doing so may help you understand the concept of interest and how it works.
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Category Archives: Lesson
The fmod() Function
The Change Due Exercise, presented earlier this year, offered a solution that uses the fmod() function. That function is to real numbers as the modulus operator is to integers, though it’s not a straight-across comparison. That’s because floating point numbers can be imprecise.
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Null Versus Empty Strings
The C language offers some delicious predicaments you may not find in other languages. Many of these odd situations involve variables, which are strongly typed in other languages. As a case in point, consider the difference between an empty string and a null string.
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Other Ways to Fix fgets() Input
The C language string-input function was once gets(). That function has become Chernobyl in that it exists but you go there only when you don’t care about your health.
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When goto Might Be Necessary
In last week’s Lesson, I covered the goto keyword the way most instructors do: I explained that it’s not needed and admonished you not to use it lest you be labeled an complete and utter dork. Still, why would such a superfluous method of program control be included if it’s awkward and unnecessary?
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Goto Hell
The only reason anyone learns about the C language keyword goto is because it’s one of the original 32 keywords. The next thing a programmer learns is to avoid it. Peril, pestilence, and pain awaits the fool who uses goto. Yea verily, if a programming Hell exists, goto is the command you use to get there.
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Wide Characters and Unicode, Part IV

String input is a weird thing when it comes to wide characters, mostly because how the heck do you type wide characters in a terminal window beyond copy-and-paste?
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Wide Characters and Unicode, Part III

Programming is a fun hobby because once you unlock and open a door, you immediately find another locked door. Normal humans would experience frustration, but a good programmer enjoys a challenge and even sees the humor in the situation. A case in point is learning how to program wide characters in C: Once you think you’ve cleared a huge hurdle, you find another, taller one right behind it.
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Wide Characters and Unicode, Part II

After you set the necessary locale for your program, you’re free to use the wide character functions defined in the wchar.h header file. For some reason, this process is poorly-documented on the Internet, which is probably why you’re here.
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Wide Characters and Unicode, Part I

At the dawn of the microcomputer era, lowercase text was considered a big deal. That’s because many home computers at the time displayed only uppercase letters. Memory was tight. Full-ASCII character generators added to the system’s cost. Yes, a microcomputer that displayed lowercase text was a big deal.
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