Add bubble sort solution

data_structures/arrays/sort_squares_of_an_array.rb

@@ -13,4 +13,36 @@
 def sorted_squares(nums)
   nums.map! { |num| num**2 }.sort
 end
+print(sorted_squares([4, -1, -9, 2]))
+
+#
+# Approach 2: is using bubble sort
+#
+
+def bubble_sort(array)
+  array_length = array.size
+  return array if array_length <= 1
+  loop do
+    swapped = false
+    (array_length - 1).times do |i|
+      if array[i] > array[i + 1]
+        array[i], array[i + 1] = array[i + 1], array[i]
+        swapped = true
+      end
+    end
+    break unless swapped
+  end
+  array
+end
+
+#
+# Time complexity analysis for Approach 1 & 2
+#
+
+def sorted_squares(nums)
+  # This takes O(n)
+  nums.map! { |num| num**2 }
+  # This can take Ο(n logn)
+  bubble_sort(nums)
+end
 print(sorted_squares([4, -1, -9, 2]))