Question

Input: A list of numbers on command line

Output: Two lists of numbers ,one with input numbers that are greater than zero and one with those that are less than zero (Ignoring zero valued numbers)

here is my code

#!/usr/bin/perl
$i++ = 0;
$j++ = 0;

while ($number = <>)
 {
        if($number<0)
          $first[$i++]=$number;
        else
          $second[$j++]=$number;

 }

 print "The numbers with value less than zero are\n";

  foreach $number (@first)
     print $number;
print "The numbers with value greater than zero are\n"

  foreach $number(@second)
     print $number;

I am getting the following silly errors which i am not able to rectify.The errors are

divide.pl: 2: ++: not found
divide.pl: 3: ++: not found
divide.pl: 5: Syntax error: ")" unexpected

Can anybody help me out with rectifying these errors please? I am new to perl script

Answer 1

The code you present will hardly compile. Loops should have {} around the main block, arrays are better created with push (or unshift), you should use strict and warnings, and you can’t do increments at the same time as assignments (e.g. $i++ = 0).

use v5.10;
use strict;
use warnings;

my (@first, @second);

while (<STDIN>) {  # <STDIN> clearer than <> in this case
    chomp;
    if ($_ < 0) {
        push @first, $_;
    } elsif ($_ > 0) {
        push @second, $_;
    }
}

say "Numbers less than zero:";
say "@first";
say "Numbers greater than zero:";
say "@second";