use strict;
use warnings;

# shift the file from args
my $file_path = shift @ARGV;

# a simple switch 
my $sw = 1;

# take indices in reverse order and skipping 2th 4th..
my @wanted_lines = grep {$sw++ and $sw % 2 == 0} reverse @ARGV;

open my $fh, '<', $file_path or die "unable to open $file_path! $!";

# in list context eat all the file at once
my @all_lines = <$fh>;

# of those all lines print a slice: the slice is @wanted_lines
# with all valuse lowered by one because indices of array start at 0
# lines starts a 1
print for @all_lines[map{$_-1}@wanted_lines];


# invoke like:
# inverted_alternated.pl file_to_read.txt 1 2 3 4