Mathematical Solutions: Multiplying by 9

We've always wanted a faster way to solve math problems. That's why we always have our handy dandy calculator. But what if you don't? You wouldn't be always carrying your calculating device everywhere, would you?

If you want to answer math problems in a snap, here's a useful math shortcut that you might wanna try before you become too dependent on calculators.. (To the point that you'd actually type 1 + 1 when the answer is already obvious).


Multiplying a number by 9.

169 X 9 is equal to? Something. You stare at the numbers with annoyance. But seriously, try and calculate it by yourself. You can write it down on a paper or mentally solve it. NO CALCULATORS!

Done? Okay. Here's the trick. You can actually solve this by using the number 10. How?
Watch:

169 X 10 = 1690
1690 - 169 = 1521

Try checking if it has the same answer as 169 x 9. It's the same, isn't it? So how did it happen?

Remember that 10 - 1 is 9.
So, basically: 169 x 9 == 169 x (10 - 1)
And we all know dividing any number to 10 is easy.

Well, it's faster if you like subtraction and subtraction is much easier than multiplication, right?


There'll be more Mathematical Solutions so stay tuned :3

A Dilemma of a Programming Student: Midterms Week part 1

Choosing a programming course because you like programming doesn't always mean fun.. Because most of the subjects you'll encounter will not even involve programming..

And so here I am, facing my PC trying to understand stuff that doesn't interest me..

But I guess they'll come handy sometime.. I mean.. I'm sure by solving the series of unfortunate events of my life using Taylor's series, I can be enlightened and be able to appreciate life..

I'm not kidding.. Life, like numbers and other mathematical entities, has a pattern :P

Well, I guess that's it for today. I have to go and become a nerd who studies math stuff D:

P.S.
I'm gonna fail.. I think D:

Programming Challenge no. 1: Sum of Multiples of 3 and 5

So I stumbled upon this site called Project Euler (It was named after Leonhard Euler who had a huge contribution in discovering infinitesimal calculus and graph theory.. Not sure if I'm thankful about his discovery.. But I guess I should since it helped improve a lot of things..)

What am I doing in Project Euler? Well, you see.. I promised to answer some programming challenges for you and as I googled the words "programming challenges", I saw this site. It's not bad actually.. I kinda like it :3

/* Warning: Must have at least basic programming experience */

So let's start with their very first challenge:

If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.
Find the sum of all the multiples of 3 or 5 below 1000.

You can go ahead and get your calculator. I'm not stopping you. However, I must warn you that you're gonna waste at least 15 minutes of your life pressing the multiples of 3 and 5.. and with a huge possibility of committing a mistake..

If I were you, I'd find an algorithm that will give me the final result. One way is solving it the programming style :P


For this challenge, I'll use C as my programming language.
I'll use Turbo C as my compiler. (This doesn't matter actually)
And my left brain to solve the problem! ('Cause for some reason, my right brain hates numbers..)

Analyzing the problem

We are asked to compute the sum of the multiples of 3 and 5. 

In their example, the multiples of 3 and 5 below 10 are given: 3, 5, 6 and 9. Adding these multiples will give us 23. We need to do the same thing. Only this time, we need to find the multiples below 1000.

It's tempting to list down all the multiples then add them together.. but that would be an inefficient way to solve this challenge..

What we need to do is analyze and take note what we need to solve the problem:

1. Only multiples of 3 and 5 are allowed.
2. Numbers like 15, 30.. etc. are multiples of 3 and at the same time, of 5.
3. Multiples should be below 1000.

So basically we need to add numbers below 1000 that are either multiples of 3 or 5 or both..

Creating the Pseudo code

Pseudo codes are useful in creating programs. Since they use simple statements instead of a specific programming language's syntax, they're very easy to read.

So here's the pseudo code for our solution:

sum as unsigned long    // We create a variable sum that holds unsigned long integers 

num as integer             // We create a counter num that will go thru 1 to 999

While num is less than 1000     // Set a condition that will prevent the loop from going beyond 1000

          if num is divisible by 3 or 5     // Check if number is a multiple of 3 or 5

             add num to sum                  // If it is, add it to sum

          add 1 to num                          // Iterate num

print sum                                          // Show output on screen

What will happen is, the computer will go through all the numbers from 0 to 999. Each will be checked if it's divisible by 3 or 5. If the number is indeed a multiple of 3 or 5, it'll be added to the sum.

Now that wasn't so hard right? Now, let's go to the exciting part: coding..

Coding

I'll just show you directly what the code is and explain each part.

void main(){
     unsigned long sum;
     int num;

This part contains the declaration statements. Here, we declared two variables: sum and num. 

sum shall contain the total value of the multiples. It's unsigned long since we expect a large number. num will be iterated from 1 to 999 so it's basically like a counter.

for(sum = 0, num = 0; num < 1000; i++){
      if((num % 3 == 0) || (num % 5 == 0)){
             sum = sum + num;
     }
}

This loop searches thru the numbers below 1000 and finds the multiples of 3. The condition uses || known as the symbol for OR because we need all the multiples of 3 and 5. Using && (known as AND) will give us only the multiples of both 3 and 5.

printf("%lu", sum);

Note:  The sum should be long since we're dealing with a huge number.

Conclusion

So? Did you understand how to solve this programming problem? If you're still having trouble comprehending the method, don't hesitate to comment.

By the way, if you want a shorter code, here's another version of it..

void main(){
     unsigned long sum;
     int num;
     for(sum = 0, num = 0; num < 1000; sum = sum + ((num % 3 == 0 || num % 5 == 0) ?           num : 0), num++);
     printf("%lu", sum);
}

The italic part of the code is using ternary operation. I'll talk about that next time. I don't want to overwhelm you.

You might be asking: So what's the answer? That would be known only if you program the code yourself :P
I don't wanna spoon-feed you with answers to the Project Euler's challenges. My goal here is to relay what I can about programming. Not become a source of direct answers from a site that challenges you to solve programming problems.

If you want your answers checked or you're having troubles with the code, you can email me directly.

I hope you learned something :)

Programming Challenges: Let's dig 'em!

I have no idea what kind of tutorials I should make.. I mean, everything is in the internet already.. So what I thought of is to find a programming challenge that requires you to program something and stuff. As I try to solve the challenge, I will also explain how the program should work

So starting from today, I'll post programming challenges that might help you analyze things when it comes to programming.

Yosh! Let's hunt for some programming puzzles to solve!

Learning Flash: Creating Point and Click games the Fun Way

/*WARNING: The video presented in this blog is now unavailable. */

Haven't really posted anything related to programming, have I?

I apologize for my lack of dedication to this blog. I would try my best to keep you updated with my journey.. I  mean, with stuff that involves programming.. and computer stuff.

Not posting in this blog doesn't mean I also lack dedication in programming. In fact, it's the contrary. I've been so focused in creating games and learning new programming languages these past few weeks.

Okay. Let's start talking variables and computer logic before I turn this whole blog into a dairy.

I've been searching for great tutorials about Flash. Why? See post Why, I Love My Work Even More. It's a personal sharing of what's up with my life. If you don't care about it, then let's proceed to the fun part!

If you're a total newbie when it comes to Flash, I suggest you google some tutorials you're comfortable with. Sometimes, there are people who understand better when reading direct to the point words. I'm part of the other side who wants to learn things in a weird manner.

But don't worry. If you want serious-talking-but-not-that-boring kind of tutorials, I highly recommend Foundation Flash. Their tutorials are very helpful and they're completely free too! I've established my Point and Click gaming instincts here.

But if you're just like me who wants to learn stuff in the weirdest way possible, then I suggest you listen to Jonbro with teh infront of it. Unfortunately, he's not into making tutorials but this video saved me from going through information-packed-yet-energy-draining tutorials.No offense to the lecturers. I just like entertaining stuff like this one:



Soo.. What do you think? Learned anything or were you just distracted with all the ranting? Well, I was distracted but I remembered all the things I needed to do after. Even though the price is to listen to a 20-minute video which can be compressed into a 10-minute one, I was glad to make the deal.

If you wanna learn more Flash tutorials, I'll get you updated with them. I'd probably post my progress in this blog together with the information I've learned. So stick around.

Why, I Love My Work Even More

Okay. First I must warn you. This a post not related to any programming facts or help. I'm simply sharing my experiences here. So if you don't wanna waste your time stalking my life, it's okay :3 You can go read the important stuff in this blog. Just browse for some tutorials.

So, where was I? Oh, right! Work!

This week has been the busiest yet the most exciting one for this year. To be honest, I'm quite pleased when my boss told me to create Flash games for their site. I'm working for them for a month already and honestly, I love my work.

However, my previous tasks don't involve programming at all. It's fine since my work is something I always do: casual gaming, plus writing and checking grammars. It's fun yet very stressful since I have to play at least 60 games per week.

The other task helped widen my web developing knowledge though. When I was searching for jobs back then, a lot of company were looking for people who know WordPress. I was thinking it would involve a lot of blogging and writing. I mean, that was how I saw WordPress before. A blogging site.

But then I was completely wrong. My boss told me to create a blog specifically for puzzle games. The site is hosted under WordPress. I've used WordPress before but I like Blogger more. So when I started tinkering my site, I was completely overwhelmed with codes and plug-ins. I thought I'd only do drag and drop in making my website. I was oh so wrong.

I had to set-up my site for a week! But it was not a wasted week. I've learned about WordPress and how you edit your own site. My PHP class didn't fail me. I've asked help from my friend, accidentallyc. You see, I like surfing but I don't like creating sites people would like to surf for. I'm into games and database analysis.

So what happened was, I've asked my friend to design my website with stuff and add creative stuff while I tinker the PHP stuff. Fortunately, when this friend of mine started his On-the-Job-training, his involvement with my WordPress adventure helped him. It's a win-win!



So I guess I've finally bore you with the past. Let's discuss the present events now!

I've been casual gaming and commenting games for a month when suddenly a door opened for me. The door to finally use my Flash and ActionScript knowledge. Well, I'm still a noob in ActionScript.

So this door opened when my boss said we need to create games we can distribute. These games will link to our site since the AI in Google can search through Flash already. This would help them rank in the search engine and I don't know why I'm ranting about this. Just know that I'm developing games to help the site gain popularity. I'll leave out the how-does-it-work for later.

Anyway, this made everything better for me. Why? Three reasons:

• My On-the-Job training is finally related to my course.
• I get to improve my game developing knowledge.
• Making games is my ambition so technically, I'm halfway in achieving my dreams. *angel singing*

And that's why I love my work even better!

*deep breathe*

Well, this is a pretty long post.

I'm surprised you read through all that boring stuff. I assume you are simply bored right now.

So.. What's up?

Woah! I just started making this blog and.. I'm starting to get lazy. Ooops..

Well, not really lazy but rather busy.

I've been doing some projects now and sad to say, most of them are not even programming.

In our Android project, I'm one of the designers. So basically, instead of a compiler, I'm using Photoshop. But most of the time, I'm using Fireworks since I'm a better vector artist.

Oh well.. I guess I need to be a programmer by myself. Is it because I'm not too good in Programming that I was assigned in Designing? Hopefully not. But in all honesty, I'm kind of glad I was not the programmer. I'm not really into mobiles.

To start my programming journey, I'll be making an HTML5 game. A simple one. So I guess I need to master my Javascript and JQuery then.

Oh, and I'm gonna post some projects and researches here just in case people need them as much as I needed them. Helping out fellow programmers, that's what we do, aye? Well, except when we're hacking each other.. that would be.. unnecessary already.

I'm gonna try and keep you update with.. uhmm.. Programming. Yes. Of course! This is why we created this blog after all.

Your program is now running..

The number of errors in programming is immense and the search for better solutions has been a tough journey for all the programmers out there. This site is the beginning of my voyage to become a better programmer and to solve the different defects in my programming. This is a personal site, by the way, and at the same time, an educational one. For every project and experience I encounter, I will post them here so I can remember my adventures in the future and for others to relate to my struggles.

So, welcome and ahoy! The voyage has been started. Let us now sail.

And yes, I may become a pirate or an explorer or a computer chip from time to time.

Sorry.. I'm not really used to long introductions :P