Illegal division by zero on very simple script

Question

A simple perl script:

#!/usr/bin/perl
$num = `sed "s/\([^ ]*\).*/\1/"`;
print "$num";

$total = `sed "s/[^ ]*\(.*\)/\1/"`;
print "$total";

$div = $num / $total;
print "div = $div \n";

When I run it:

$ echo 4 10 | ./test.pl 
4 10
Illegal division by zero at ./test.pl line 11.

Answer 1

Change the code like this and the answer will be obvious:

#!/usr/bin/perl

$num = `sed "s/\([^ ]*\).*/\1/"`;

print "num = $num\n";

$total = `sed "s/[^ ]*\(.*\)/\1/"`;

print "total = $total\n";

$div = $num / $total;

print "div = $div\n";