Here is one way:

#! perl
use strict;
use warnings;
use Data::Dumper;

my @array = (1, 'Matthew',
             2, 'Mark',
             3, 'Luke',
             4, 'John',
             5);

my @copy = @array;
my @list;

while (@copy)
{
    push( @list, shift @copy );
    shift @copy;    # throw the string away
}

print Dumper(\@list);
[download]

Output:

$VAR1 = [
          1,
          2,
          3,
          4,
          5
        ];
[download]

HTH,