exercism-67 Allergies

Author: kumar91gopi

README.md

@@ -284,6 +284,7 @@ solution of many challenges of [Leetcode](https://leetcode.com/), [Exercism](htt
 64. [Binary Search](https://github.com/kumar91gopi/Algorithms-and-Data-Structures-in-Ruby/blob/master/exercism/binary_search.rb)
 65. [Matching Brackets](https://github.com/kumar91gopi/Algorithms-and-Data-Structures-in-Ruby/blob/master/exercism/matching_brackets.rb)
 66. [All Your Base](https://github.com/kumar91gopi/Algorithms-and-Data-Structures-in-Ruby/blob/master/exercism/all_your_base.rb)
+67. [Allergies](https://github.com/kumar91gopi/Algorithms-and-Data-Structures-in-Ruby/blob/master/exercism/allergies.rb)
 
 <a name="leetcode"/>
 

exercism/allergies.rb

@@ -0,0 +1,69 @@
+# Problem: https://exercism.org/tracks/ruby/exercises/allergies
+
+# Solution 1
+class Allergies
+    ALLERGY_VAL_FOOD_MAP = {
+              1  => 'eggs',
+              2  => 'peanuts',
+              4  => 'shellfish',
+              8  => 'strawberries',
+              16 => 'tomatoes',
+              32 => 'chocolate',
+              64 => 'pollen',
+              128 => 'cats'
+            }
+    
+    def initialize(score)
+      @score = score.to_s(2).reverse
+      @allergies = []
+    end
+
+    def allergic_to?(item)
+      self.list if @allergies.empty?
+      @allergies.include?(item)
+    end
+
+    def list
+      debug "score#{@score}"
+      ALLERGY_VAL_FOOD_MAP.each do |key,val|
+        @allergies.push(val) if @score[Math.log(key,2)] == '1'
+      end
+      @allergies
+    end
+end
+
+# Solution 2
+class Allergies
+    ALLERGY_VAL_FOOD_MAP = {
+                               1  => 'eggs',
+                               2  => 'peanuts',
+                               4  => 'shellfish',
+                               8  => 'strawberries',
+                               16 => 'tomatoes',
+                               32 => 'chocolate',
+                               64 => 'pollen',
+                               128 => 'cats'
+                          }
+    
+    def initialize(score)
+      @score = score%256
+      @list = []
+    end
+    
+    def allergic_to?(item)
+      self.list if @list.empty?
+      @list.include?(item)
+    end
+
+    def list
+      num = 2**7
+      while num > 0
+        if @score >= num
+          @list.push(ALLERGY_VAL_FOOD_MAP[num])
+          @score-=num
+        end
+        num/=2
+      end
+      @list.reverse!
+    end
+end