From f2e91c8d7acb8af31fddad5b990fd9c200692066 Mon Sep 17 00:00:00 2001
From: Manuel Bustillo <bustikiller@bustikiller.com>
Date: Sun, 10 Nov 2024 18:55:04 +0100
Subject: [PATCH 1/2] Run perturbations in both orders

---
 app/services/vns/engine.rb       | 11 +++++++++--
 spec/services/vns/engine_spec.rb | 13 +++++++++++++
 2 files changed, 22 insertions(+), 2 deletions(-)
 create mode 100644 spec/services/vns/engine_spec.rb

diff --git a/app/services/vns/engine.rb b/app/services/vns/engine.rb
index 00f2c80..65ceb71 100644
--- a/app/services/vns/engine.rb
+++ b/app/services/vns/engine.rb
@@ -2,6 +2,13 @@
 
 module VNS
   class Engine
+    class << self
+      def sequence(elements)
+        elements = elements.to_a
+        (elements + elements.reverse).chunk(&:itself).map(&:first)
+      end
+    end
+
     def target_function(&function)
       @target_function = function
     end
@@ -23,12 +30,12 @@ module VNS
 
       puts "Initial score: #{@best_score.to_f}"
 
-      @perturbations.each do |perturbation|
+      self.class.sequence(@perturbations).each do |perturbation|
         puts "Running perturbation: #{perturbation.name}"
         optimize(perturbation.new(@best_solution))
       end
 
-      @best_solution 
+      @best_solution
     end
 
     private
diff --git a/spec/services/vns/engine_spec.rb b/spec/services/vns/engine_spec.rb
new file mode 100644
index 0000000..974f342
--- /dev/null
+++ b/spec/services/vns/engine_spec.rb
@@ -0,0 +1,13 @@
+require 'rails_helper'
+
+module VNS
+  RSpec.describe Engine do
+    describe '.sequence' do
+      it { expect(described_class.sequence([])).to eq([]) }
+      it { expect(described_class.sequence([1])).to eq([1]) }
+      it { expect(described_class.sequence([1, 2])).to eq([1, 2, 1]) }
+      it { expect(described_class.sequence([1, 2, 3])).to eq([1, 2, 3, 2, 1]) }
+      it { expect(described_class.sequence([1, 2, 3, 4])).to eq([1, 2, 3, 4, 3, 2, 1]) }
+    end
+  end
+end
-- 
2.47.1


From fe91f75ec077b1369c8f67fcf6bf09840612c7ef Mon Sep 17 00:00:00 2001
From: Manuel Bustillo <bustikiller@bustikiller.com>
Date: Sun, 10 Nov 2024 17:57:29 +0000
Subject: [PATCH 2/2] Add copyright notice

---
 spec/services/vns/engine_spec.rb | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/spec/services/vns/engine_spec.rb b/spec/services/vns/engine_spec.rb
index 974f342..d4064f6 100644
--- a/spec/services/vns/engine_spec.rb
+++ b/spec/services/vns/engine_spec.rb
@@ -1,3 +1,5 @@
+# Copyright (C) 2024 Manuel Bustillo
+
 require 'rails_helper'
 
 module VNS
-- 
2.47.1