Here's the first thing I thought of: 

#!/usr/bin/perl

my $s1 = "//depot/Efp/Celox/CELOX-3.5.0/CeloxStart.sln";
my $s2 = "//depot/Efp/Celox/MAIN/CeloxStart.sln";

@s1 = split "/", $s1;
@s2 = split "/", $s2;

my $i = 0;  $i++ while $s1[$i] eq $s2[$i];  # find end of common begin
+ning
my $j = -1; $j-- while $s1[$j] eq $s2[$j];  # find beginning of common
+ end

print join("/", @s1[$i..(@s1+$j)]), "\n";
print join("/", @s2[$i..(@s2+$j)]), "\n";

[download]
There are probably better ways :-)

update: Though I have to wonder why you're worrying about efficiency. You only have to do this for "thousands of records". Is that really "thousands of records per second" or something where efficienct execution really matters? Or are you just prematurely optimizing?

duff

In reply to Re: Selecting the difference between two strings by duff
in thread Selecting the difference between two strings by qazwart

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