You've got two mistakes in the posted code. From split

split /PATTERN/,EXPR,LIMIT
split /PATTERN/,EXPR
split /PATTERN/
split

So you mean @parse = split("/", $url); not @parse = split($url, "/");. As well, array indexing starts from 0, not 1, so @parse[$parse]; is out-of-bounds -- see Variable names. You can fix this either with $parse = $#parse; or $parse = @parse - 1;.

Corrected version:

$url = "http://www.bing.com/default.aspx";
@parse = split "/", $url;
$parse = @parse-1;
$FileName = @parse[$parse];
print $FileName;
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