Merge pull request #55 from cassiosantana/feature/6-minimum-sum

Feature/6 minimum sum

lib/algorithms_ruby.rb

@@ -3,6 +3,7 @@
 require "ffaker"
 
 require_relative "algorithms_ruby/base"
+require_relative "algorithms_ruby/minimum_sum"
 require_relative "algorithms_ruby/binary_search"
 require_relative "algorithms_ruby/bubble_sort"
 require_relative "algorithms_ruby/count"

lib/algorithms_ruby/minimum_sum.rb

@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+# Implementation of the algorithm found in:
+# https://www.geeksforgeeks.org/minimum-sum-choosing-minimum-pairs-array/
+
+module AlgorithmsRuby
+  class MinimumSum < Base
+    def initialize(arr)
+      @arr = arr
+      super
+    end
+
+    def call
+      minimum_value * repetitions
+    end
+
+    private
+
+    def minimum_value
+      @arr.min
+    end
+
+    def repetitions
+      @arr.size - 1
+    end
+  end
+end

spec/algorithms_ruby/minimum_sum_spec.rb

@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+RSpec.describe AlgorithmsRuby::MinimumSum do
+  let(:array) { [2, 4, 1, 3] }
+  subject { described_class.new(array) }
+
+  describe ".call" do
+    it "returns the correct minimum sum" do
+      expect(subject.call).to eq(3)
+    end
+  end
+
+  describe "#minimum_value" do
+    it "returns the minimum value" do
+      expect(subject.send(:minimum_value)).to eq(1)
+    end
+  end
+
+  describe "#repetitions" do
+    it "returns the correct number of repetitions" do
+      expect(subject.send(:repetitions)).to eq(3)
+    end
+  end
+end
+