Do you realize what "accessibility" refers to in the context of this article? Congratulations on being 100% off-topic.
This is about making OpenOffice.org easier to use for the disabled. Mozilla is jumping on board, too. It requires no action by Microsoft, and will add a coherent accessibility scheme to some of the most visible open source projects.
Wow, I feel better after seeing this information. And to think, I was a bit nervous thinking about how dangerous information could be used by stupid people. Reading through these there are errors that a high-school chemistry student could spot. The rest is just a collection of useless facts that pale when compared to the wealth of information on dangerous topics to be found in the wikipedia. These are just accumulated ramblings of people with inflated views of their own self-importance.
Reminds me of the various files I collected back on the day (anyone remember gopher?) and compared. I found a half-dozen sets of conflicting instructions for nitro-glycerin that ranged from completely ineffective to possible but unreasonably dangerous for the experimenter.
Who knows, maybe these files are just big brother's way of weeding out stupid terrorists early.
I have a ~160 year old math textbook that goes from basic addition to financial calculations to square root/cube root. I've never seen another method for computing a cube root by hand...
<reality> I'm so ashamed... but I couldn't resist the joke. </reality>
<absurdity> My daughter will only allow one of her dolls in her play crib at a time. I have patented this process and will be selling implementations of the "Dolly-Exclusion Priciple" in the near future. </absurdity>
Congratulations, you know what detonation is. However, you apparently think that just because something can be detonated that it cannot be burned.
Nitroglycerin may be burned, although the expansion will not be as powerful as if it were detonated. In fact it can explode from the heat generated when creating it (ie: adding the glycerine to the nitric/sulfuric acid mix too quickly).
And in response to another post: The sulfuric acid is required as a catalyst. Nitric acid alone will not allow for the production of nitroglycerin, gun cotton, TNT, etc (you can nitrate most organic compounds...)
I got a version of this at a job interview, only they left out the part that the sticks can only touch at their ends. They DID say that the sticks could not overlap, a subtle relaxation of the problem. I came up with a solution that was valid by their rules but not the solution to the parent's question.
What I take from the minimum rulers you give is that they prove that if you have a ruler that can measure every distance from 1 to 11 that it will either be longer than 11 units or it will have more than one way to measure at least one of the lengths. Looking at a table of optimal golomb rulers (google) I see that any optimal golomb ruler longer than 6 units (4 marks at 0-1-4-6) is not "complete," or in other words it cannot measure every unit distance up to and including its length.
Finally, someone pointing out the reason why so many people are getting suckered. Everyone thinks that fridge magnets are doing "work" and are "power"ful when they are simply producing a force.
The humanities used to refer to the studies that a person needed to survive in modern society (and not get suckered), and this included math. I think that today physics should be added to this category as well.
Well, yeah, I didn't do a very good job of simplifying the prisoner's job. Lets try this again:
You are a prisoner. There are three (or at least no more than 5) colors "in play", so you hold up that many fingers. Let's say the first finger is red, the second is green, and the last one blue.
You start out pointing to your first finger and start scanning the people in front of you. When you see a green dot move over one finger, and when you see a blue dot move over two fingers. (Of course you will wrap around from the third finger to the first when you run out of fingers)
Now that you have the total for the colors in front of you we need to take the negative of this number (unless you are the first prisoner to be asked, you poor shmuck^H^H^H^H^H^H^H^H^H^H^Hbrave soul). This is the best I can figure out, negatives are strange in modulo arithmetic: From the finger you are currently on, count your way back to the first finger. However many fingers you counted down, count down the same amount again (wrapping to the last finger as the first move, of course).
When the first person answers count up again the number of finger for that color. Now for the rest of the time count down for each answer given. When you are asked the question it will be at your fingertips (almost sorry for the pun).
First, assign each color a number to each of the colors (start at zero as all of the arithmetic will be modulo the number of colors). The prisoners can do this the night before.
m = Number of colors n = Number of prisoners
The first person to be asked adds up the color values from the other (n - 1) prisoners. He then says the color that corresponds to the value of ((sum of n-1 colors) % m) and has a 1 in m chance of surviving.
The second person in line takes the value of the color that the first person answered and then subtracts (mod m) the sum of the values of the colors in front of him. The difference is the value of the color on the back of his head.
The rest of the prisoners in line take the value of the answer by the first person and subtract the sum of the values they can see. In order to get the value of the color on the back of his head he also subtracts the answers of each person behind him (except the first person, of course).
There you go (assuming you are still tracking this thread after so long:). If this answer isn't clear let me know.
Your answer only works if there are two colors, although it is an interesting way to think through the problem. The simplest way to put a hole in your solution is to point out that the colors (that can be seen) could be evenly distributed 33-33-33. Then someone gets screwed, and fast.
The even/odd tracking is interesting, but to track the three colors you really need to use a method with three states. Also, don't forget about the problem of expanding your algorithm to an arbitrary number of prisoners and colors. (This really is pretty easy to do once you solve the three color problem, although perhaps not for the prisoners)
BTW, if this is really annoying you (but in a bad way:) let me know and I will leave the solution.
While your observation about the unlucky guy in the back is correct, the "real" answer does not depend on the timing, tone, pitch, etc of the answers. I almost, and probably should have, put this in the original post.
Think about this from the standpoint of information: What does each person know?
1 - The colors on each person in front of them 2 - The answers of each person behind them
BIG HINT: This information and a bit of modulo arithemetic is can save everyone except for the first person.
I love when I can flex some of my neurons, and here is a puzzle that I loved hearing. It made the rounds in the Physics circles a couple of years ago, I believe. I'll try to check back soon with the solution.
Also, feel free to put any other really good puzzles in this thread!
------------Begin Story------------------ There are 100 prisoners being held captive. One day they are told that some of them will die the next day in a trial. They are told to plan tonight for the following:
The prisoners will be lined up, one behind the other, so that each prisoner can see all of the people in front of him. A red, green, or blue dot will be placed on the back of each prisoner's head, but the prisoner will not know the color on the back of their own head (or, of course, the colors on the heads of the prisoners behind him). Then the captors will start at the back of the line and ask the question "What is the color on the back of your head?". The prisoner must answer with one of the colors, and any other answer, or answering out of turn, will result in everyone being executed. Everyone can hear the answers of the people to come before them. After the question has been asked of every prisoner, the prisoners who answered incorrectly will be executed.
Question: What is the most effective plan that the prisoners can come up with, and how many people will die with this plan?
Extra credit: Expand the plan to include an arbitrary number of prisoners and colors. Now how many people will die?
I don't imagine there are many warez servers with 2MB RAM and 100MB free HD space... Besides that, I would think that as many versions as the underlying libraries have gone through that current cracking tools wouldn't know what to do with something so outdated.
Maybe you should create an archive of old Linux cracking tools just to even the playing field?
While the thickness of the tile is obviously unknown, the article says the the tiles are approximately 5x11 inches. This is within 2% of having a 4:9 ratio. Of course this is only for the one tile in the story. The picture of a tile from DC (in the pictures linked to from below the one picture in the main article) looks to be more along the lines of a 4:7 ratio, though, so it was possibly just a coincidence with the one tile.
Am I the only person with a strong urge to write a program to put every number in the US on the list?:) A little wget in a loop, an email parser that waits for messages from register@donotcall.gov... would hardly be impossible.
That would be an incredibly huge finger to give the telemarketers
The FEW out-of-control situations are either caused by stuck throttle linkages or drivers hitting the wrong pedal.
I would like to point out that the idle bypass valve (controlled by the computer, not the pedal) CAN cause the car to rev uncontrollably. This is probably what happened. If it is wide open (usually a mechanical problem, not one with the computer) then the car will act as if it is nearly floored. I have actually had this problem on two seperate cars.
Both problems are solved by simply SWITCHING THE FUCKING IGNITION OFF...
Agreed. Also, most of the cars I have driven are manuals, so I just disengage the clutch. No loss of vacuum (quite the opposite) for braking.
Note- if you turn the ignition off, only turn it to the accessory position, or you'll be finding it mighty hard to steer.
I think you are confused here. Most cars have the power steering driven by a belt, so as soon as the engine is stopped you loose power assist. If you have a car with the steering pump driven by an electric motor THEN leaving the key in ACC might help, unless it is on the same circuit as the ignition system...
Slashdot Mirror
A cannibal passed his brother in the woods.
Are you serious? You don't need a physical switch, you can just unplug one set of cables and plug in another set...
Mass does not depend upon the acceleration it is placed under...
Do you realize what "accessibility" refers to in the context of this article? Congratulations on being 100% off-topic.
This is about making OpenOffice.org easier to use for the disabled. Mozilla is jumping on board, too. It requires no action by Microsoft, and will add a coherent accessibility scheme to some of the most visible open source projects.
Wow, I feel better after seeing this information. And to think, I was a bit nervous thinking about how dangerous information could be used by stupid people. Reading through these there are errors that a high-school chemistry student could spot. The rest is just a collection of useless facts that pale when compared to the wealth of information on dangerous topics to be found in the wikipedia. These are just accumulated ramblings of people with inflated views of their own self-importance.
Reminds me of the various files I collected back on the day (anyone remember gopher?) and compared. I found a half-dozen sets of conflicting instructions for nitro-glycerin that ranged from completely ineffective to possible but unreasonably dangerous for the experimenter.
Who knows, maybe these files are just big brother's way of weeding out stupid terrorists early.
I have a ~160 year old math textbook that goes from basic addition to financial calculations to square root/cube root. I've never seen another method for computing a cube root by hand...
It reads:
lol no its not its inconvenient data
<reality>
I'm so ashamed... but I couldn't resist the joke.
</reality>
<absurdity>
My daughter will only allow one of her dolls in her play crib at a time. I have patented this process and will be selling implementations of the "Dolly-Exclusion Priciple" in the near future.
</absurdity>
Congratulations, you know what detonation is. However, you apparently think that just because something can be detonated that it cannot be burned.
Nitroglycerin may be burned, although the expansion will not be as powerful as if it were detonated. In fact it can explode from the heat generated when creating it (ie: adding the glycerine to the nitric/sulfuric acid mix too quickly).
See http://en.wikipedia.org/wiki/Nitroglycerin
And in response to another post: The sulfuric acid is required as a catalyst. Nitric acid alone will not allow for the production of nitroglycerin, gun cotton, TNT, etc (you can nitrate most organic compounds...)
I got a version of this at a job interview, only they left out the part that the sticks can only touch at their ends. They DID say that the sticks could not overlap, a subtle relaxation of the problem. I came up with a solution that was valid by their rules but not the solution to the parent's question.
What I take from the minimum rulers you give is that they prove that if you have a ruler that can measure every distance from 1 to 11 that it will either be longer than 11 units or it will have more than one way to measure at least one of the lengths. Looking at a table of optimal golomb rulers (google) I see that any optimal golomb ruler longer than 6 units (4 marks at 0-1-4-6) is not "complete," or in other words it cannot measure every unit distance up to and including its length.
originally he was going to answer the question.
Finally, someone pointing out the reason why so many people are getting suckered. Everyone thinks that fridge magnets are doing "work" and are "power"ful when they are simply producing a force.
The humanities used to refer to the studies that a person needed to survive in modern society (and not get suckered), and this included math. I think that today physics should be added to this category as well.
since i haven't rtfa ...
It was a joke. Laugh.
... but if I was massively paralyzed ...
:)
Am I the only one that thought of a beowolf cluster of quadriplegics? Parallelize the paralyzed!
(Is this crass enough to be modded down? Let's see
Well, yeah, I didn't do a very good job of simplifying the prisoner's job. Lets try this again:
You are a prisoner. There are three (or at least no more than 5) colors "in play", so you hold up that many fingers. Let's say the first finger is red, the second is green, and the last one blue.
You start out pointing to your first finger and start scanning the people in front of you. When you see a green dot move over one finger, and when you see a blue dot move over two fingers. (Of course you will wrap around from the third finger to the first when you run out of fingers)
Now that you have the total for the colors in front of you we need to take the negative of this number (unless you are the first prisoner to be asked, you poor shmuck^H^H^H^H^H^H^H^H^H^H^Hbrave soul). This is the best I can figure out, negatives are strange in modulo arithmetic: From the finger you are currently on, count your way back to the first finger. However many fingers you counted down, count down the same amount again (wrapping to the last finger as the first move, of course).
When the first person answers count up again the number of finger for that color. Now for the rest of the time count down for each answer given. When you are asked the question it will be at your fingertips (almost sorry for the pun).
First, assign each color a number to each of the colors (start at zero as all of the arithmetic will be modulo the number of colors). The prisoners can do this the night before.
m = Number of colors
n = Number of prisoners
The first person to be asked adds up the color values from the other (n - 1) prisoners. He then says the color that corresponds to the value of ((sum of n-1 colors) % m) and has a 1 in m chance of surviving.
The second person in line takes the value of the color that the first person answered and then subtracts (mod m) the sum of the values of the colors in front of him. The difference is the value of the color on the back of his head.
The rest of the prisoners in line take the value of the answer by the first person and subtract the sum of the values they can see. In order to get the value of the color on the back of his head he also subtracts the answers of each person behind him (except the first person, of course).
There you go (assuming you are still tracking this thread after so long:). If this answer isn't clear let me know.
Chris
Your answer only works if there are two colors, although it is an interesting way to think through the problem. The simplest way to put a hole in your solution is to point out that the colors (that can be seen) could be evenly distributed 33-33-33. Then someone gets screwed, and fast.
The even/odd tracking is interesting, but to track the three colors you really need to use a method with three states. Also, don't forget about the problem of expanding your algorithm to an arbitrary number of prisoners and colors. (This really is pretty easy to do once you solve the three color problem, although perhaps not for the prisoners)
BTW, if this is really annoying you (but in a bad way:) let me know and I will leave the solution.
While your observation about the unlucky guy in the back is correct, the "real" answer does not depend on the timing, tone, pitch, etc of the answers. I almost, and probably should have, put this in the original post.
Think about this from the standpoint of information: What does each person know?
1 - The colors on each person in front of them
2 - The answers of each person behind them
BIG HINT:
This information and a bit of modulo arithemetic is can save everyone except for the first person.
I love when I can flex some of my neurons, and here is a puzzle that I loved hearing. It made the rounds in the Physics circles a couple of years ago, I believe. I'll try to check back soon with the solution.
Also, feel free to put any other really good puzzles in this thread!
------------Begin Story------------------
There are 100 prisoners being held captive. One day they are told that some of them will die the next day in a trial. They are told to plan tonight for the following:
The prisoners will be lined up, one behind the other, so that each prisoner can see all of the people in front of him. A red, green, or blue dot will be placed on the back of each prisoner's head, but the prisoner will not know the color on the back of their own head (or, of course, the colors on the heads of the prisoners behind him). Then the captors will start at the back of the line and ask the question "What is the color on the back of your head?". The prisoner must answer with one of the colors, and any other answer, or answering out of turn, will result in everyone being executed. Everyone can hear the answers of the people to come before them. After the question has been asked of every prisoner, the prisoners who answered incorrectly will be executed.
Question: What is the most effective plan that the prisoners can come up with, and how many people will die with this plan?
Extra credit: Expand the plan to include an arbitrary number of prisoners and colors. Now how many people will die?
Only royalty and people with tapeworms can use the self-referencing "we".
(Badly paraphrased from a forgotten source)
I don't imagine there are many warez servers with 2MB RAM and 100MB free HD space... Besides that, I would think that as many versions as the underlying libraries have gone through that current cracking tools wouldn't know what to do with something so outdated.
Maybe you should create an archive of old Linux cracking tools just to even the playing field?
While the thickness of the tile is obviously unknown, the article says the the tiles are approximately 5x11 inches. This is within 2% of having a 4:9 ratio. Of course this is only for the one tile in the story. The picture of a tile from DC (in the pictures linked to from below the one picture in the main article) looks to be more along the lines of a 4:7 ratio, though, so it was possibly just a coincidence with the one tile.
I need to get together some friends and stage muggings/beatings/hit and runs/etc in front of local camaras.
Am I the only person with a strong urge to write a program to put every number in the US on the list? :) A little wget in a loop, an email parser that waits for messages from register@donotcall.gov... would hardly be impossible.
That would be an incredibly huge finger to give the telemarketers
The FEW out-of-control situations are either caused by stuck throttle linkages or drivers hitting the wrong pedal.
I would like to point out that the idle bypass valve (controlled by the computer, not the pedal) CAN cause the car to rev uncontrollably. This is probably what happened. If it is wide open (usually a mechanical problem, not one with the computer) then the car will act as if it is nearly floored. I have actually had this problem on two seperate cars.
Both problems are solved by simply SWITCHING THE FUCKING IGNITION OFF...
Agreed. Also, most of the cars I have driven are manuals, so I just disengage the clutch. No loss of vacuum (quite the opposite) for braking.
Note- if you turn the ignition off, only turn it to the accessory position, or you'll be finding it mighty hard to steer.
I think you are confused here. Most cars have the power steering driven by a belt, so as soon as the engine is stopped you loose power assist. If you have a car with the steering pump driven by an electric motor THEN leaving the key in ACC might help, unless it is on the same circuit as the ignition system...