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A little guideline  Go to the Impossible n'est pas français challenge

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The question is simple: is it possible to do this challenge without generating a huge list of primes before attempting?

P.S. Is it a special algorithm?
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It is a special algorithm, but that won't help you.

Take everything into account, the title, the number of points assigned, number of solvers, etc. Sometimes things look harder than they actually are.

Good luck.
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So as far as I understand, the algorithm is not important in this challenge?

Title doesn't help, since it says it is possible, despite it doesn't look like it.
3 points mean it shouldn't be difficult.
19 solvers mean it is quite difficult.
Considering POST is easily doable, the difficulty is concentrated in the factorization scheme.

I'll try using ecliptic curve and make sure the calculations use 100% CPU power, but what bothers me is the http connection initiation, which is ~1s and is really annoying when you have only 8 seconds and a huge number to factorise.
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I analyzed the length of few numbers that are generated (~200) and i realized that there is a very small rate of numbers that can be factorized in that amount of seconds : like 4-5 / 100 .Even Pollard's Rho takes 'a lot' for such big number.So it is there a specific way intended to use or?
Edit : Now i passed it.Nice idea.
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It is planned to tag the challenges with categories one day.

This challenge would perfectly fit into the exploit section ;)
The geeks shall inherit the properties and methods of object earth.
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i think this can be done using linux's bc(calculator.)...
I Would Love TO Change The World But They Wont Give Me The Source Code....
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Quote from vs4vijay

i think this can be done using linux's bc(calculator.)...

dont think so ;P
Last edited by dxer - Feb 09, 2010 - 20:21:30
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RE: A little guideline
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I'm trying to factorize 3979472463314875085840002857228600720282384996148243543352143582302262781295828387891781441314971190160417811911956695502719284157232823856745170795069181463088768150823640408439 at the moment.
Quote from Output
Correct would have been "233371896958934483413852469328454047497967773738436383518876274982852741524656654197321563532648518587251529755179966181612599845399444534861453916936649223911587974762215384448371"

which should have been [233371896958934483L, 413852469328454047L, 497967773738436383L, 518876274982852741L, 524656654197321563L, 532648518587251529L, 755179966181612599L, 845399444534861453L, 916936649223911587L]
These nine factors are all greater than 10^17 but smaller than 10^18, the difference between the biggest and the smallest is about 6*10^17 ... wow ...

pyecm found two of these nine in about 5 minutes ... as I solved the challenge meanwhile, I'll stop pyecm.

Nice challenge Happy
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