Add answer

answer.rb

@@ -0,0 +1,70 @@
+require 'pry'
+
+lines = File.read("numbers.csv").lines
+
+# 1. sum of first line - 569
+def sum_one_line l
+  numbers_as_strings = l.chomp.split ","
+  running_total = 0
+  numbers_as_strings.each do |n|
+    running_total += n.to_f
+  end
+  return running_total
+end
+
+s = sum_one_line lines.first
+puts "Sum of the first line is: #{s}"
+
+# 2. sum of all the lines - 10170
+running_total = 0
+lines.each do |line|
+  s = sum_one_line line
+  running_total += s
+end
+
+# lines.map { |l| l.split(",").map { |n| n.to_i } }.flatten.reduce(:+)
+
+puts "Sum of file: #{running_total}"
+
+
+# 3. how many numbers in this file
+
+all_tokens = lines.map { |l| l.split(",") }.flatten
+all_numbers = all_tokens.map { |t| t.to_i }
+
+number_of_numbers = 0
+lines.each do |i|
+  number_of_numbers += i.split(",").count
+end
+
+# Other functional options
+n2 = lines.map { |l| l.split(",") }.flatten.count
+n3 = lines.map { |l| l.split(",").count }.reduce :+
+n4 = all_numbers.count
+
+
+# 4. how many are even? divisible by 7?
+
+evens = []
+all_numbers.each do |n|
+  if n.even?
+    evens.push n
+  end
+end
+
+# evens.count => 102 even numbers
+
+sevens = []
+all_numbers.each do |n|
+  if n % 7 == 0
+    sevens.push n
+  end
+end
+
+# sevens.count => 28
+
+# Functionally -
+all_numbers.select { |n| n.even? }.count
+all_numbers.select { |n| n % 7 == 0 }.count
+
+binding.pry