William Reardon’s Blog

I recently stumbled on Project Euler, a series of various mathematical/programming challenges. A lot of them can be solved quite easily in Perl, such a problem 5:

What is the smallest number divisible by each of the numbers 1 to 20?

I’m sure there’s a more elegant solution, but I figured, heck that’d be easy to brute force. So I whipped up a few lines of Perl. Here’s my first pass:

#!/usr/bin/perl -w

use strict;
my $value = 0;

my @divsors = reverse(2 .. 20);
EULER: while (1) {

  $value += 20;

  print “$value…\n” unless ($value % 1000000);
  for my $i (@divsors) {

    next EULER if ($value % $i);

  }
  last;

}

Anything like while(1) always makes me worry about an infinite loop, so I threw in the status line & watched it.

Happily, there was no infinite loop & it terminated.

0.0001 seconds later I realized what an idiot I was.

The programs goes through all the hard work of figuring out the value and then… well, nothing.

I forgot to add a line to print it out the final value.

So, in a nutshell, my first attempt worked — all the heavy lifting bits were correct — but it was worth naught as I overlooked a trivial bit.

Sadly, this is apt microcosm of my life.

This entry was posted on Saturday, January 19th, 2008 at 7:58 pm and is filed under shared-idoicy. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.