Create ch-2.pl

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diff --git a/challenge-050/user-person/perl/ch-2.pl b/challenge-050/user-person/perl/ch-2.pl
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+#!/usr/bin/env perl
+
+###########################################################################
+# script name: ch-2.pl                                                    #
+#                                                                         #
+# https://github.com/user-person                                          #
+#                                                                         #
+# https://perlweeklychallenge.org/blog/perl-weekly-challenge-050/         #
+#                                                                         #
+# Noble Integer                                                           #
+# You are given a list, @L, of three or more random integers between 1    #
+# and 50. A Noble Integer is an integer N in @L, such that there are      #
+# exactly N integers greater than N in @L. Output any Noble Integer       #
+# found in @L, or an empty list if none were found.                       #
+#                                                                         #
+# An interesting question is whether or not there can be multiple Noble   #
+# Integers in a list.                                                     #
+#                                                                         #
+# For example,                                                            #
+#                                                                         #
+# Suppose we have list of 4 integers [2, 6, 1, 3].                        #
+#                                                                         #
+# Here we have 2 in the above list, known as Noble Integer, since there   #
+# are exactly 2 integers in the list i.e.3 and 6, which are greater than  #
+# 2.                                                                      #
+#                                                                         #
+# Therefore the script would print 2.                                     #
+#                                                                         #
+###########################################################################
+
+use strict;
+use warnings;
+
+sub nobleInt {
+    my @ints = sort { $a <=> $b } @_;
+    my %seen = ();
+    for (my $i = 0; $i <= $#ints; ++$i) {
+        my $count = 0;
+      MOV:
+        for (my $j = 0; $j <= $#ints; ++$j) {
+            next MOV if $i == $j;
+            ++$count if $ints[$i] < $ints[$j];
+        }
+        $seen{ $ints[$i] }++ if $count == $ints[$i];
+    }
+    return keys %seen;
+}
+
+my $input = "[2, 6, 1, 3]";
+
+if (@ARGV) {
+    $input = "@ARGV"
+} else {
+    print "default input: $input\n";
+}
+
+$input    =~ s{[][, ]+}{ }g;
+$input    =~ s{\A\s+|\s+\Z}{};
+my @L     = split m{ }, $input;
+
+my @nobleInteger = nobleInt @L;
+
+if ( @nobleInteger ){
+    print "Noble integer: $nobleInteger[0]\n";
+} else {
+    print "No noble integer.\n";
+}