vi - branches

lib/binary_to_decimal.rb

@@ -4,6 +4,30 @@
 # The least significant bit is at index 7.
 # Calculate  and return the decimal value for this binary number using
 # the algorithm you devised in class.
+# index_array = [0, 1, 2, 3, 4]
+# binary_array = [1, 0, 0, 1, 1, 0, 0, 1]
+# #we want to take the length minus one, and that will be what 2 is to the power of at the first element
+
+# (1 * 2^7) + (0 * 2^6) ... + (1 * 2^0)
+# = 153
+#So i could break this down by saying .. 
+#I want to find the length of the total array (.length)
+#Assign .length to a variable, length
+#I want to loop through every element in the array
+#I want to multiply each element by 2 to the power of length - 1
+#I want to put all of those new values into a new array
+#I want to get the sum of all of those new numbers 
+
+
 def binary_to_decimal(binary_array)
-  raise NotImplementedError
+  size = binary_array.length
+  total = 0
+
+  binary_array.each_with_index do |number, index|
+    total += number * ( 2 ** (size - index - 1) )
+  end 
+  return total
 end
+
+
+puts binary_to_decimal([1, 0, 0, 1, 1, 0, 0, 1])