perl - 为什么我的用于打印行号前缀的行的 Perl 脚本不起作用？

Question

我打算打开一个文本文件并读取行。并在其前面添加带有行号的字母“pp”。

文本文件如下。

39828513 39829926 1413 hsa-mir-6719
41252946 41254434 1488 hsa-mir-6889
62331112 62332604 1492 hsa-mir-4758

And I want to have the output as follows:

pp1 39828513 39829926 1413 hsa-mir-6719
pp2 41252946 41254434 1488 hsa-mir-6889
pp3 62331112 62332604 1492 hsa-mir-4758

I have written a code but I don't feel its working fine.

use strict;
use warnings;
open (fh, " < file.txt") || die ;
while ($line=<fh>)
{
 chomp ($line);
    for (my $i=1; $i <= ($#line); $i++)
    {
    print "pp$i\t$line";
    }
}

Answer 1

利用 $. 变量:

print "pp$. $_" while <>;