Hi!

Line 34 is 

       $b[$i] = $a[$i] + $a[$j];

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And the error is Use of uninitialized value in addition (+) at yanghui.pl line 34..

So obviously either $a[$i] or $a[$j] are undefined.

Now lets have a look at $i and $j: 

       for($i=1;$i<=$k;$i++){              # $k = $#a + 1;
                $j = $i - 1;

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So $j goes from 0 to the number of the last element of $a. And $i goes from 1 to the last element + 1!

The element $a["last element + 1"] is undefined, and that's the reason for your error.

The solution is simple: just let your loop process one element less: 

       for($i=1;$i<$k;$i++)

[download]

HTH, Rata

In reply to Re: problem in my sub partition by Ratazong
in thread problem in my sub partition by PhillipHuang

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