- Tidied up solution to Stealthy Numbers by Robert DiCicco.

1 files changed, 16 insertions, 22 deletions

diff --git a/challenge-143/robert-dicicco/perl/ch-2.pl b/challenge-143/robert-dicicco/perl/ch-2.pl
index 3bd0ea1527..8f9027516f 100644
--- a/challenge-143/robert-dicicco/perl/ch-2.pl
+++ b/challenge-143/robert-dicicco/perl/ch-2.pl
@@ -4,10 +4,11 @@ use strict;
 use warnings;
 use ntheory qw/divisors/;
 use IO::Prompter;
+use 5.30.0;
 
 ### Author: Robert DiCicco
-### Date: 13-DEC-2021
-### Challenge #143 Stealthy Number
+### Date: 15-DEC-2021
+### Challenge #143 Stealthy Number v 2.0
 
 # initialize vars
 # array to hold list of divisors
@@ -16,9 +17,6 @@ my @final = ();
 # sum of initial set of divisors
 my $target = 0;
 
-# limit to single digits
-my $limit = 10;
-
 # Get number from user
 my $inp = prompt 'Input the number : ', -integer => [ 1 .. 999 ];
 chomp($inp);
@@ -28,30 +26,26 @@ $inp = int($inp);
 my @d = divisors($inp);
 
 # get divisors and their sums
-foreach(sort @d){
-    #skip if divisor is greater than $limit
-    next if($_ >= $limit);
-
+foreach(@d){
     my $val = $inp / $_;
+    # skip the opposite pair (e.g. 3,4  but skip 4,3)
+    next if ($val > $_);
+    my $digit_sum = $val + $_;
+
+    if($target == 0){
+        $target = $digit_sum;
+        push(@final,$val,$_);
+    }
 
-    # is single digit
-    if($val < $limit) {
-        my $digit_sum = $val + $_;
-        if($target == 0){
-            $target = $digit_sum;
-            push(@final,$val,$_);
-        }
-
-        if($digit_sum == ($target - 1)){
-            push(@final,$val,$_);
-            last;
-        }
+    if($digit_sum == ($target + 1)){
+        push(@final,$val,$_);
+        last;
     }
 }
 
 # if we have 4 divisors that meet the criteria, print
 if(scalar(@final) == 4){
-    print("$final[0] x $final[1] = $final[2] x $final[3] and $final[0] + $final[1] = $final[2] + $final[3] + 1\n");
+    print("$final[2] x $final[3] = $final[0] x $final[1] and $final[2] + $final[3] = $final[0] + $final[1] + 1");
 } else {
     print("Not Stealthy!\n");
 }