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Harut

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quote:
Originally posted by Domino:

SAS, could your write this down in English please ?


Domino,

 

my English is very bad, so I’m sorry for mistakes.

 

The problem:

 

It is given any natural number N > 1.

 

The RECURSIVE definition next number is:

 

................ N / 2, if N is even number

NextN =

................ 3*N + 1, if N is odd number

 

Prove that after finite steps NextN = 1:

 

Example: N = 7

 

NextN = {22, 11, 34, 17, 52, 26, 13, 40, 20, 10, 5, 16, 8, 4, 2, 1}

 

[ October 08, 2002, 09:05 AM: Message edited by: SAS ]

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Another problem (author V. Arnold ).

 

Definition: Tow natural prime number( N, M ) is CONNECTED PAIR if abs(N-M) = 2.

 

Prove that the number of CONNECTED PAIR is infinite.

 

Example:

 

(1,3)(3,5)(5,7)(11,13)(17,19)(29,31)(41,43) (59,61)(71,73)(87,89)(89,91) (101,103) etc.

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  • 2 weeks later...

This guy named Harut is preparing to sail around the world. Unfortunately, he is not very organized and is not sure what he should bring on the trip. Here is some important information about his voyage:

 

Harut is going to leave on a Saturday at 5:00 AM.

 

His boat travels an average of 528 miles per 24 hour day.

 

The voyage is 24,684 miles long.

 

Harut uses 3.5 gallons of water per day.

 

He consumes 3/4 of a pound of dried meat per day except on Fridays (he plans to substitute three fish each Friday).

 

He has a shot(28 grams) of Ararat Konyak every night before going to bed to sleep well.

 

He plans to stop on days 4 and 5 on an island to visit a friend Domino. During these 48 hours he plans to eat with the island residents and will use the food and water from the island, thereby conserving his supplies.

 

He also plans to stop on days 27 and 28 on an island to visit another friend Sip. During these 48 hours he plans to eat with his Sip's family and will use the food and water they provide, thereby conserving his supplies. But unlike Domino, Sip does not want to share his cognac so he has to et some from teh boat.

 

On what day of the week will he return?

What time of day will he return?

How much water will he need?

How much fish will he need?

How much meat will he need?

How much Ararat Konyak will he consume?(my addition )

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  • 4 months later...

here is a fun puzzle I got the other day.

 

There are 5 houses in 5 different colors.

In each house lives a person with a different nationality.

The 5 owners drink a certain type of beverage, smoke a certain brand of cigar, and keep a certain pet.

No owners have the same pet, smoke the same brand of cigar, or drink the same beverage.

 

Hints:

 

The Brit lives in the red house.

The Swede keeps dogs as pets.

The Dane drinks tea.

The green house is on the left of the white house.

The green homeowner drinks coffee.

The person who smokes Pall Mall rears birds.

The owner of the yellow house smokes Dunhill.

The man living in the center house drinks milk.

The Norwegian lives in the first house.

The man who smokes Blend lives next to the one who keeps cats.

The man who keeps the horse lives next to the man who smokes Dunhill.

The owner who smokes Bluemaster drinks beer.

The German smokes prince.

The Norwegian lives next to the blue house.

The man who smokes Blend has a neighbor who drinks water.

 

The question is: Who owns the fish?

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quote:
Originally posted by Azat:

On what day of the week will he return?

What time of day will he return?

How much water will he need?

How much fish will he need?

How much meat will he need?

How much Ararat Konyak will he consume?(my addition )


Sunday

11:00 pm

163.625 gallons

3

34.3125 pounds

1365 grams

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quote:
Originally posted by Sip:

Nice!!! You do realize you are in a very select few 2% in the world that could possibly solve this? I have heard several times that this was proposed by Einstein and that he claimed that 98% of the people would not be able to solve it

 

How true that is, I don't know.


I was told that as well, but it seems too easy to figure it out. I would bet most(60, 70, 80%) people would figure this puzzle out given enough time.

 

But I would go on now thinking that I am part of that special 2%

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Wow, I didn't even think I'd get it right!

 

Sipan, trial and error

 

code:
Norwegian       Dane        Brit        German      Swede

 

yellow blue red green white

 

water tea milk coffee beer

 

Dunhill Blend Pall Mall Prince Bluemaster

 

cats horse birds dogs


So the German must have the fish. Is this ok? How would you have done it? Is there a formula for this type of problem?
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Nice!!! You do realize you are in a very select few 2% in the world that could possibly solve this? I have heard several times that this was proposed by Einstein and that he claimed that 98% of the people would not be able to solve it

 

How true that is, I don't know.

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I may have posted this before:

 

You have 2 lengths of fuse that are guaranteed to burn for precisely 1 hour each. Other than that fact, you know nothing; they may burn at different (indeed, at variable) rates, they may be of different lengths, thicknesses, materials, etc.

 

How can you use these two fuses to time a 45 minute interval?

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  • 1 month later...

The four people in this puzzle all competed in different classes of dog agility at a recent competition. The competitions all required the dogs to run over jumps, through tunnels and various other obstacles in as quicker time as possible. Each had a different result - one came first, one third, one fourth and one ninth. All four dogs were each of a different breed.

 

Can you work out who handled which dog, at what level each competed, the place each finished in and the breed of each dog?

 

 

1. If Tiff finished first then Domino finished fourth.

2. If Domino finished fourth then Jago is a collie.

3. If Nairi competed in the Senior class then she finished third.

4. If Nairi competed in Novice then she finished fourth.

4. The dog that finished ninth was an alsatian. This was either Jago, in which case Jago competed in the Elementary class, or this was Kelly, in which case Domino handled Kelly.

5. Harut won Starters.

6. If Harut's dog is called Patti then Patti is a labrador otherwise Patti is a collie.

7. Stormy's dog is called Jago.

8. If Jago finished fourth then she competed in the Novice class otherwise she competed in the Senior class.

9. If Patti finished first then Domino's dog is an alsatian otherwise Domino's dog is a collie.

10. If Nairi's dog is a doberman then Nairi finished fourth otherwise Nairi finished third.

 

Handler's Names: Nairi, Harut, Domino and Stormy

Dog's Names: Tiff, Patti, Jago and Kelly

Breed: Alsatian, Collie, Labrador and Doberman

Level: Starters, Elementary, Novice or Senior

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During the recent cipher convention, a binary code contest took place. The contest consisted of a binary code transmission where the spaces between the letters were missing and there was no punctuation. Each letter of the alphabet was translated into its binary equivalent based on its position in the alphabet, a=1, b=10,...,z=11010. What is the answer to the question being asked?

 

110011101001000100110011100110011110110

101100101100110010011101101001111010111

001010010000101011101011010110010110011

010010001111101011111000101001001101001

011111111010111001001000101110010000100

111010011100111011101100110011100111011

000011001011000110101101100111010010011

111111010111100011010010011001111111110

101100001100101011001111111110101

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2

 

Azat, you can't believe how much time I wasted on that binary problem! It is much harder than it seems at first... I figured I could solve it easily by writing a short program ... well, I wrote the program in 10 minutes and went to eat hoping it would find the solution ... came back realizing it had filled up my hard drive and crashed !!!!! The embarassing thing is that my little brother solved it faster than me. Damn he is GOOD.

 

:clap:

 

I was estimating that there could be a lot of possibilities but I didn't think there would be that many valid texts that can be decoded from that message :o

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So Sipan, how do you get to the answer? I don't understand the binary system and which numbers represent which letters.

 

Azat, is this right?

 

Starters        Elementary      Novice      Senior

Harut            Domino                 Stormy      Nairi

Patti             Kelly                 Jago          Tiff

Labrador      Alsatian           Doberman  Collie

1st               9th                  4th              3rd

 

I was kidding in the above btw, except for the despising dogs part. I'm more of a bug person (kerm unem, and a lot of them :)).

Edited by nairi
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Nairi jan, all you need to know about binary is this is what each letter corresponds to. The rest is basic pattern matching. For example, "10100" in the message could represent either "t" or "bd".

 

a 1
b 10
c 11
d 100
e 101
f 110
g 111
h 1000
i 1001
j 1010
k 1011
l 1100
m 1101
n 1110
o 1111
p 10000
q 10001
r 10010
s 10011
t 10100
u 10101
v 10110
w 10111
x 11000
y 11001
z 11010

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Ok Sip jan, any clues how you guys got the answer?

 

I have the answer only because I was given the answer, but I was trying to think of a clever programmatic way of figuring out the answer and I have not been able to.

 

I have tried many ways and am now thinking of grabbing a flat file dictionary and trying to first find the words in the sentence followed by the fillers.

 

So throw us some hints prior to me spending another night trying to get a clever solution.

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Azat jan, you are asking me to explain how the human mind works ... which I can't. After looking at it for a while, you will see the solution as in most puzzles. This is one of those things that a simple computer hack will NOT get the job done. The program needs to be much more intelligent in the way it processes the input.

 

HERE is the basic source to my program. It may crash since it uses recursion and the size is set to max. But if you want to use it to parse substrings of the long message, it works well.

 

You may notice a few things there that I used to speed up stuff. Like during the recursion, I keep track of the last character parsed. This way, I can get rid of uncommon pairs like yy or bd or db or things like that. However, since words don't have spaces, it may be that you get rid of a pair that can actually occur (end of a word and beginning of another).

 

The way I solved the problem was to go substring at a time. As a hint, there is a clear way to split the string at the 'p' characters :)

 

If you want more hints, let me know. If my code is impossible to understand, also let me know. I wrote it in a quick/dirty way so it is by no means a "good" code. It was just the easiest way to write it for me. Three things to keep in mind:

 

1) I parse from the end of the string back ... for various reasons.

2) I decided to keep track of the message in an array (msg)

3) I consider the characters in reverse order since it's harder to fit a "t" than b's and d's for example.

 

I was using command line parameters to specify what index to what index it should parse ... but I left that and all my other optimization hacks out of it so there will be some chance for someone to understand what's going on.

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