A simple PERL script to count the number of zero bits in a given byte.

1. This PERL script counts the number of zero bits in a given input byte. For examplae if the input is 254 the result is 1.
2. In language like C it is simple. There are boolean operations, which make the task easy to implement.
3. To facilitate matters in PERL, I used conversion from decimal to binary.
4. There are a few ways to do it. I used:
   $b=sprintf("%b", $_[0]);
   


5. The rest of the job is achieved by simply counting the zeros using PERL substr.



6. The script is listed below:
   The first parameter is $_[0] is the input byte. The second one namly, $_[1], holds the output result.
   
   sub num_of_zero {
     my $b="";
     $j="";
     $l="";
     $b=sprintf("%b", $_[0]);
     $l=length($b);
     $_[1]=8-$l;
     for($j=0; $j < $l; $j++) {
       if(substr($b, $j, 1) == 0) {$_[1]++;}
     }
     print("$_[0] $b $_[1]\n");
   }
   
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