in reply to largest number inside array/hash
Hi Anonymous Monk.
In an attempt to display the 'syntactically rich' nature of the perl language, I have taken the liberty of including yet another array oriented solution:
#!/usr/bin/perl w
use strict;
my @array = ( 33, 56, 3, 2, 67, 101, 218, 4, 17 );
my @nums = sort { $a <=> $b } @array;
print "The largest number is: $nums[$#nums]\n";
Output:
C:\>perl pg8.pl
The largest number is: 218
C:\>
Hope this helps,
Katie
Re: Re: largest number inside array/hash by TomDLux (Vicar) on Apr 07, 2004 at 07:35 UTC 
Think back to second year of college, when you took that Algorithms course.
A good sort such as quick sort is O( N logN ), poor ones such as bubble sort are O( N^2 ). A max() function requires a single pass through the list, and so is O( N ). It would be silly to do N log N  N ( i.e. N (log N  1) ) operations more than you need to.

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In practice, on small data sets, the penalty is a factor of 10 or so. Which is similar to the penalty from using Perl. If you can get a good constant, the log(n) might be paid for. (Real example. Wavelet algorithms tend to be O(n) while the FFT is O(n*log(n)). But the FFT has a better constant.) At some point worrying about how the computer spends a millisecond of time itself becomes silly.
Me, I tend to treat logarithmic factors as noise unless I'm trying to squeeze performance. The difference between linear and quadratic I care about. O(n) vs O(n*log(n)) I don't. I know them, I just don't care much.
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Re^2: largest number inside array/hash by Anonymous Monk on Aug 17, 2012 at 17:09 UTC 
Hi
Nice elegant solution.
but i guess this would work too
#!/usr/bin/perl w
use strict;
my @array = ( 33, 56, 3, 2, 67, 101, 218, 4, 17 );
my @nums = sort { $b <=> $a } @array;
print "The largest number is: $nums[0]\n";
 [reply] [d/l] 
