Hello wisdom masters, I have the following two strings: 
$str1 = "12345 ABC 987 MNO";
$str2 = "      CDE";

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And I need to merge the strings as to get: 
$str = "12345 CDE 987 MNO";

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So, kind of a XOR at a character level if you want.

Being looong strings and maaaany in the files I am processing, I look for your wise input to make it as time efficient as possible, much more than the "obvious" solution: 
my @arr1 = split //, $str1;
my @arr2 = split //, $str2;
foreach (my $i=0;$i<@arr1;$i++) {
        if ($arr2[$i]) { # we do have something in the second string
                if (($arr1[$i] ne " ") and ($arr2[$i] eq " ")) {
                        $arr2[$i] = $arr1[$i];
                }
        } else { #$str2 is empty now, so copy all
                $arr2[$i] = $arr1[$i];
        }
}
print join "",@arr2,"\n";

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Thanks everyone,
Lian

In reply to merging strings (xor at char level?) by csebe

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