Hi Monks, I am just puzzled about how to reset the <> operator in while loop. For example, I have two levels loops like this: 
 while (<FILE1>){
       chomp;
       my @array1=split;
       my $a1=$array1[1];
       my $a2=$array1[2];
           ......
         while (<FILE2>){   #wrong, cannot iterate all the lines
          my @array2=split;
          my $b1=$array2[0];
          my $b2=$array2[1];
             if ($a1 eq $b1){
              .......}
             else {......}
         }
    }

[download]
The problem for the above code is that it cannot iterate all the lines of file2. When the first level of while start its second line, the <> operater of the second level while was already at the end of the file2. Of course I can use "for" loops instead of second while loop. But is there a method that I can reset the position of <> operator and make it to re-iterate the file2 for every line of file1(the first while loop)? Thank you.

In reply to how to reset the input operater in while loop? by lightoverhead

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