从perl文件中仅打印一行中由制表符分隔的十个单词

Question

#! /bin/usr/perl
print "Enter your database name: \n";
chomp($db=<STDIN>);
open(R1,"$db")||die("error");
while ($line1=(<R1>)) {
    $l1=$line1;
    @arr1= split("  ",$l1);
    for $i=(0..9)
    {
        print  "@arr1[$i] \t";
        print join (@arr1), "\n";
    }
}
close(R1);
exit;

I want to have only ten words or (number also counted as a word) but what I am getting is only first the ten words are printed rest of the file is blank.

Desired output:

1 my name is abcde fg

your name is micheal and you study in class 5

Answer 1

The initial problem with your code is syntax errors. The second problem is that you have not told Perl to help you write better code. Almost all Perl code should have use strict; use warnings; use strict; use warnings; , so your code should start

#! /bin/usr/perl
use strict;
use warnings;

The use strict; will mean you must declare all the variables used, but that is a good thing. The two lines will also point out the syntax errors.

The only Perl programs that should not have use strict; and use warnings; are those where their author knows exactly why are being omitted and can explain the reasons to other people.

Answer 2

perl -wnlaF'\t' -E 'say join "\t", @F[0 .. (9 <= $#F ? 9 : $#F)]' input.txt > output.txt