perl/commas.pl: comma-ize numbers greater than 999

perl/commas.pl

@@ -0,0 +1,19 @@
+#!/usr/bin/env perl
+
+foreach $arg (0..$#ARGV) {
+  my $num = int($ARGV[$arg]);
+  my $fmt = "", $cnt = 0;
+
+  while($num > 0) {
+    $fmt = ($num % 10) . $fmt;
+
+    if(++$cnt % 3 == 0 and $num >= 10) {
+      $fmt = "," . $fmt;
+    }
+
+    use integer;
+    $num /= 10;
+  }
+
+  print "$fmt\n";
+}