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Thread: I need help for this time complexity measurment?

  1. #1
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    Default I need help for this time complexity measurment?

    HTML Code:
    for(int i= 0,j= 0; i< n; i++,j++ )
    {
    
      for(int a= 0,b= 0; a< n; a++,b++ )
       {			
               1 statement goes   here...  
    			  
       }
    		 
    }
    Is this O(n2) or O(n4) or what ?? Can any of you convince me about this.

    Hope you got what i want.


  2. #2
    Super Moderator Sean4u's Avatar
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    Default Re: I need help for this time complexity measurment?

    I didn't know you could put comma-separated statements in the for-loop in Java. When did that creep in?

    i and a control the loops, j and b are dependent on them. A nest of two loops is [insert answer here]. Note that using this rule of thumb on loops is only valid - or at best only gives you a lower bound to your time complexity - if the "1 statement goes here" is an O(1) statement.

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    Administrator copeg's Avatar
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    Default Re: I need help for this time complexity measurment?

    This thread has been cross posted here:

    http://www.java-forums.org/advanced-java/48592-i-need-help-time-complexity.html

    Although cross posting is allowed, for everyone's benefit, please read:

    Java Programming Forums Cross Posting Rules

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    Super Moderator helloworld922's Avatar
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    Default Re: I need help for this time complexity measurment?

    Quote Originally Posted by Sean4u View Post
    I didn't know you could put comma-separated statements in the for-loop in Java. When did that creep in?
    Comma Operator

    As far as I know, it's probably been in there from day one (I know it's present in the C/C++ language).

  5. The Following User Says Thank You to helloworld922 For This Useful Post:

    Sean4u (September 16th, 2011)

  6. #5
    Super Moderator Sean4u's Avatar
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    Default Re: I need help for this time complexity measurment?

    been in there from day one
    I had never previously heard of a 'comma operator' - it's nasty! Thanks for that.

  7. #6
    Super Moderator helloworld922's Avatar
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    Default Re: I need help for this time complexity measurment?

    Quote Originally Posted by Sean4u View Post
    I had never previously heard of a 'comma operator' - it's nasty! Thanks for that.
    Yeah, it should be avoided if possible

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