solve efficiently

This is a discussion on solve efficiently within the C Programming forums, part of the General Programming Boards category; i need to solve this equation efficiently m+n-gcd(m,n)=N i.e, when N is given i need to find NUMBER OF PAIRS ...

  1. #1
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    solve efficiently

    i need to solve this equation efficiently

    m+n-gcd(m,n)=N

    i.e, when N is given i need to find NUMBER OF PAIRS of m,n that satisify the equation

    N<10^6

    can any 1 help !!!

  2. #2
    Woof, woof! zacs7's Avatar
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    Are you familiar with the Euclidean Algorithm? http://mathworld.wolfram.com/EuclideanAlgorithm.html

    That's generally what these sort of questions are getting at.

  3. #3
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    please

    can u repost explaining it please

    my campus has blocked that site ( stupid proxy restrictions )

    sorry of the trouble
    thank u very much

  4. #4
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    gcd ?

    i think i need to reduce two things to get proper runtime

    i should not be looping for each & every case & also shud not use recursion to calculate gcd ( euclids algo will help)

    but what about the for loops ??

    some 1 help

    thank u

  5. #5
    Kernel hacker
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    Why don't you google for Euclidian Algorithm then - there are probably hundreds of places where it is descrbed. [And I'm pretty sure that you are not SUPPOSED to come up with that solution by yourself - that's what books about algorithms are for, if you aren't able to use the web].

    --
    Mats
    Compilers can produce warnings - make the compiler programmers happy: Use them!
    Please don't PM me for help - and no, I don't do help over instant messengers.

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