So, I got a fever. Not a good sign of course. My roommate started spreading germs when he got a cold, and although I tried to stay away from him, getting a cold is almost inevitable. I'm obviously not too happy about that.
Here's one interesting thing I find about getting a fever, and that is I will have visions of future. This last happened when I was in grade 2. I got a fever and I saw a crew of people coming into the house and videotaping stuff. Indeed, months later, my home in Taiwan was used as a place/setting for a drama.
This time, it happened much sooner. I had a dream about the dinner today (some sort of noodle) and when I went to dinner, it was exactly the same as I saw in my dream.
Weird isn't it?
Saturday, September 29, 2007
Wednesday, September 26, 2007
PE Locker (!)
Ok, it seriously stinks. I forgot when it started, but days ago, I open the PE locker door, and a pungent smell came out immediately. Maybe someone left some of their gym socks in there? I don't know.
Saturday, September 22, 2007
Tic Tac Toe
Of course everybody knows how to play, but did you know the ultimate winning strategy?
If you are the first person, you will always win.
First move: in any corner. DO NOT put in the center, or else it will usually be a tie.
Second move: if the opponent put in the center, put on the opposite corner of your first move. You will win, because there are 2 places where you can place to win.
place on the ?, opponent can't block 2 at once
x ?
oo
x
Second move (continued): if opponent place on a corner, then place on an adjacent corner. Your opponent must block it, and then it will leave a place open for you to put the winning move.
ex:
place on the ? to win.
xox
o ?
If you are the first person, you will always win.
First move: in any corner. DO NOT put in the center, or else it will usually be a tie.
Second move: if the opponent put in the center, put on the opposite corner of your first move. You will win, because there are 2 places where you can place to win.
place on the ?, opponent can't block 2 at once
x ?
oo
x
Second move (continued): if opponent place on a corner, then place on an adjacent corner. Your opponent must block it, and then it will leave a place open for you to put the winning move.
ex:
place on the ? to win.
xox
o ?
Thursday, September 20, 2007
How many digits are in x!
x!, as you know, would be x * (x-1) * (x-2) * ... * 3 * 2 * 1.
Obviously we don't want to calculate x! and count the digits if it would be a very large number.
For example, calculating 1000! isn't a very effective way to get the number of digits.
Logarithmic rules can be applied in these situations.
log(ab) = log(a) + log(b)
And we want to calculate log(1000!) before calculating 1000! first.
log(1000!) = log(1000) + log(999) + log(998) + log(997) + ... + log(3) + log(2) + log(1)
Still 1000 numbers to add, but much easier than trying to multiply 1000 numbers together.
With a little bit of calculation, we find the answer 2567.60464422213, which means after multiplying numbers 1 to 1000, we will get a 2568-digit number
Obviously we don't want to calculate x! and count the digits if it would be a very large number.
For example, calculating 1000! isn't a very effective way to get the number of digits.
Logarithmic rules can be applied in these situations.
log(ab) = log(a) + log(b)
And we want to calculate log(1000!) before calculating 1000! first.
log(1000!) = log(1000) + log(999) + log(998) + log(997) + ... + log(3) + log(2) + log(1)
Still 1000 numbers to add, but much easier than trying to multiply 1000 numbers together.
With a little bit of calculation, we find the answer 2567.60464422213, which means after multiplying numbers 1 to 1000, we will get a 2568-digit number
Monday, September 17, 2007
Board Games
I'm loosing all the time on various boardgames now. I don't really care, but here's something I learned... it is... always play conservatively; protect from loosing before trying to proceed with your "winning" plan. Hate loosing, but half of it is luck.
Friday, September 14, 2007
Breaking a Locker
It seems like lockers aren't as secure as we think. There seems to be 60 x 60 x 60 = 216000 combinations, but in reality, the margin of errors make it only 20 x 20 x 20 = 6000 combinations.
Every number has a margin of error. It could be 2 back, 1 forward, 1 back, 2 forward, or 3 back. Smart people would just try multiples of 3. Another thing also make it easier, and that is, on the third number, you can keep turning and trying, until you get to the correct combination (of course if you turn 2 times clockwise, it will reset).
For example, if a locker combination is 26, 7, 38, you can go for 24, 9, 35, and it will still open. Because of the property of the third number (you don't have to reset to try a different third number), we only have to focus on the first and second number. There are 20 x 20 = 400 combinations. It will take 1 minute to try the third number.
Therefire, a maximum of 400 minutes is required to crack a locker. Averagely, it will take 200 minutes, which is about 3 hours. If you are lucky, it might take less than 20 minutes.
Every number has a margin of error. It could be 2 back, 1 forward, 1 back, 2 forward, or 3 back. Smart people would just try multiples of 3. Another thing also make it easier, and that is, on the third number, you can keep turning and trying, until you get to the correct combination (of course if you turn 2 times clockwise, it will reset).
For example, if a locker combination is 26, 7, 38, you can go for 24, 9, 35, and it will still open. Because of the property of the third number (you don't have to reset to try a different third number), we only have to focus on the first and second number. There are 20 x 20 = 400 combinations. It will take 1 minute to try the third number.
Therefire, a maximum of 400 minutes is required to crack a locker. Averagely, it will take 200 minutes, which is about 3 hours. If you are lucky, it might take less than 20 minutes.
Thursday, September 13, 2007
French
Uh, I have to say that French is my... *euphemistically* least favourite subject. During the French classes for the pass few days, we ain't allowed to speak English. (ne pas parle en Anglais!) I don't understand a word the teacher says; it sounds like some mumble jumble to me. I almost slept off during class because it was so boring. Then, for homework, we had to watch this &*@#$ video and learn the words/vocabularies. I *can* pick up a few word in the video, but 99% of them are new to me, and I didn't get the vocabulary sheet. Je deteste le Francais!
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