Add Perl solution

5 files changed, 160 insertions, 0 deletions

diff --git a/challenge-241/paulo-custodio/Makefile b/challenge-241/paulo-custodio/Makefile
new file mode 100644
index 0000000000..c3c762d746
--- /dev/null
+++ b/challenge-241/paulo-custodio/Makefile
@@ -0,0 +1,2 @@
+all:
+	perl ../../challenge-001/paulo-custodio/test.pl
diff --git a/challenge-241/paulo-custodio/perl/ch-1.pl b/challenge-241/paulo-custodio/perl/ch-1.pl
new file mode 100644
index 0000000000..407c471494
--- /dev/null
+++ b/challenge-241/paulo-custodio/perl/ch-1.pl
@@ -0,0 +1,71 @@
+#!/usr/bin/env perl
+
+# Challenge 241
+#
+# Task 1: Arithmetic Triplets
+# Submitted by: Mohammad S Anwar
+#
+# You are given an array (3 or more members) of integers in increasing order
+# and a positive integer.
+#
+# Write a script to find out the number of unique Arithmetic Triplets satisfying
+# the following rules:
+#
+# a) i < j < k
+# b) nums[j] - nums[i] == diff
+# c) nums[k] - nums[j] == diff
+#
+# Example 1
+#
+# Input: @nums = (0, 1, 4, 6, 7, 10)
+#        $diff = 3
+# Output: 2
+#
+# Index (1, 2, 4) is an arithmetic triplet because both  7 - 4 == 3 and 4 - 1 == 3.
+# Index (2, 4, 5) is an arithmetic triplet because both 10 - 7 == 3 and 7 - 4 == 3.
+#
+# Example 2
+#
+# Input: @nums = (4, 5, 6, 7, 8, 9)
+#        $diff = 2
+# Output: 2
+#
+# (0, 2, 4) is an arithmetic triplet because both 8 - 6 == 2 and 6 - 4 == 2.
+# (1, 3, 5) is an arithmetic triplet because both 9 - 7 == 2 and 7 - 5 == 2.
+
+use Modern::Perl;
+
+# parse args
+sub usage { return "Usage: $0 -nums n n n ... -diff n\n"; }
+
+my(@nums, $diff);
+while (@ARGV) {
+    if ($ARGV[0] eq "-nums") {
+        shift;
+        while (@ARGV && $ARGV[0] !~ /^-/) {
+            push @nums, shift;
+        }
+    }
+    elsif ($ARGV[0] eq "-diff") {
+        shift;
+        $diff = shift;
+    }
+    else {
+        die usage();
+    }
+}
+if (!@nums || !$diff) { die usage(); }
+
+# compute
+my $count = 0;
+for my $i (0 .. $#nums-2) {
+    for my $j ($i+1 .. $#nums-1) {
+        for my $k ($j+1 .. $#nums) {
+            $count++ if ($nums[$j] - $nums[$i] == $diff &&
+                         $nums[$k] - $nums[$j] == $diff);
+        }
+    }
+}
+
+# output
+say $count;
diff --git a/challenge-241/paulo-custodio/perl/ch-2.pl b/challenge-241/paulo-custodio/perl/ch-2.pl
new file mode 100644
index 0000000000..8c598ef885
--- /dev/null
+++ b/challenge-241/paulo-custodio/perl/ch-2.pl
@@ -0,0 +1,67 @@
+#!/usr/bin/env perl
+
+# Challenge 241
+#
+# Task 2: Prime Order
+# Submitted by: Mohammad S Anwar
+#
+# You are given an array of unique positive integers greater than 2.
+#
+# Write a script to sort them in ascending order of the count of their prime
+# factors, tie-breaking by ascending value.
+# Example 1
+#
+# Input: @int = (11, 8, 27, 4)
+# Output: (11, 4, 8, 27))
+#
+# Prime factors of 11 => 11
+# Prime factors of  4 => 2, 2
+# Prime factors of  8 => 2, 2, 2
+# Prime factors of 27 => 3, 3, 3
+
+use Modern::Perl;
+
+sub is_prime {
+    my($n) = @_;
+    return 0 if $n <= 1;
+    return 1 if $n <= 3;
+    return 0 if ($n % 2)==0 || ($n % 3)==0;
+    for (my $i = 5; $i*$i <= $n; $i += 6) {
+        return 0 if ($n % $i)==0 || ($n % ($i+2))==0;
+    }
+    return 1;
+}
+
+sub prime_factors {
+    my($n) = @_;
+    my @factors;
+    my $p = 0;
+    while ($n > 1) {
+        do { $p++; } while (!is_prime($p));
+        while ($n % $p == 0) {
+            push @factors, $p;
+            $n /= $p;
+        }
+    }
+    return @factors;
+}
+
+# parse args
+@ARGV>0 or die "ch-2 n n...\n";
+my @nums = @ARGV;
+
+# process
+@nums = map { $_->[0] }
+        sort {
+            my(@fa) = @{$a->[1]};
+            my(@fb) = @{$b->[1]};
+            if (@fa != @fb) { return scalar(@fa) - scalar(@fb); }
+            for my $i (0 .. $#fa) {
+                if ($fa[$i] != $fb[$i]) { return $fa[$i] - $fb[$i]; }
+            }
+            return 0;
+        }
+        map {[$_, [prime_factors($_)]]} @nums;
+
+# output
+say "@nums";
diff --git a/challenge-241/paulo-custodio/t/test-1.yaml b/challenge-241/paulo-custodio/t/test-1.yaml
new file mode 100644
index 0000000000..b4593c8ed1
--- /dev/null
+++ b/challenge-241/paulo-custodio/t/test-1.yaml
@@ -0,0 +1,10 @@
+- setup:
+  cleanup:
+  args:     -nums 0 1 4 6 7 10 -diff 3
+  input:
+  output:   2
+- setup:
+  cleanup:
+  args:     -nums 4 5 6 7 8 9 -diff 2
+  input:
+  output:   2
diff --git a/challenge-241/paulo-custodio/t/test-2.yaml b/challenge-241/paulo-custodio/t/test-2.yaml
new file mode 100644
index 0000000000..2f50da7c69
--- /dev/null
+++ b/challenge-241/paulo-custodio/t/test-2.yaml
@@ -0,0 +1,10 @@
+- setup:
+  cleanup:
+  args:     11 8 27 4
+  input:
+  output:   11 4 8 27
+- setup:
+  cleanup:
+  args:     11 27 8 4
+  input:
+  output:   11 4 8 27