Learn to Program Chapter 12 exercises

Ex12.rb

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+
+# 1. One billion seconds!
+OBS = Time.local(1979, 9, 18, 9, 0) + 10**9
+puts OBS
+
+# Happy birthday
+puts "What year were you born in?"
+year = gets.chomp
+
+puts "Which month of #{year}? Please provide a number i.e. 1 for Jan"
+month = gets.chomp
+
+puts "Now we also need to know the day please. Also as an integer..."
+day = gets.chomp
+
+birth_date = Time.local(year.to_i, month.to_i, day.to_i)
+current_date = Time.new
+age = (current_date - birth_date)/365/24/60/60
+puts "You are #{age.to_i} years old."
+puts "Spank!" * age.to_i
+
+# 2. PARTY LIKE IT'S ROMAN_TO_INTEGER MCMXCIX
+rom_hash = { M: 1000, D: 500, C: 100, L: 50, X: 10, V: 5, I: 1 }
+
+puts "Enter roman numerals and I'll convert it to an integer"
+rom = gets.chomp
+
+rom_arr = rom.split('')
+int_arr = []                                      # [1000, 100, 1000, 10, 100, 1, 10]
+
+rom_arr.each {|r| int_arr << rom_hash[r.to_sym]}  # [10, 1, 100, 10, 1000, 100, 1000]
+int_arr.reverse!
+
+total = int_arr[0]
+index1 = 0
+index2 = 1
+arr_len = int_arr.length - 1
+
+while index2 <= arr_len
+  if int_arr[index1] <= int_arr[index2]
+    total += int_arr[index2]
+    index1 += 1
+    index2 += 1
+  else
+    total -= int_arr[index2]
+    index1 += 1
+    index2 += 1
+  end
+end
+
+puts total
+
+# 3. BIRTHDAY HELPER
+require 'yaml'
+# This part was to create a file in th current folder.
+=begin
+cal = { 'Christopher Alexander' =>  'Oct  4, 1936',
+        'Christopher Lambert' =>    'Mar 29, 1957',
+        'Christopher Lee' =>        'May 27, 1922',
+        'Christopher Lloyd' =>      'Oct 22, 1938',
+        'Christopher Pine' =>       'Aug  3, 1976',
+        'Christopher Plummer' =>    'Dec 13, 1927',
+        'Christopher Walken' =>     'Mar 31, 1943',
+        'The King of Spain' =>      'Jan  5, 1938'}
+
+filename = 'birth_cal.txt'
+
+File.open filename, 'w' do |f|
+  f.write cal.to_yaml
+end
+=end
+
+filename = 'birth_cal.txt'
+content = File.read filename
+yaml_obj = YAML:: load content
+
+puts "Please enter the full name of the following people to retrieve their birthday & age"
+puts yaml_obj.each { |name, date| puts name }
+resp = gets.chomp
+
+if yaml_obj.include?(resp)
+  puts yaml_obj[resp]
+else
+  puts "I don't recognise that name"
+end