while (my $line = <INFILE>) {
    my @line = split /\t/, $line;

    my %hash = (
        key0 => $line[0],
        key1 => $line[1],
        key2 => $line[2],
        key3 => $line[3],
        key4 => $line[4],
    );

    print "Key 3 is $hash{key3}\n";

    push @lines_of_file, \%hash;
}

##</code><code>##

while (my $line = <INFILE>) {
    my %hash;
    @hash{qw(key0 key1 key2 key3 key4)} = split /\t/, $line;

    print "Key 3 is $hash{key3}\n";

    push @lines_of_file, \%hash;
}