first commit

.tool-versions

@@ -0,0 +1 @@
+ruby 2.5.0

Gemfile.lock

@@ -1,49 +1,55 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    addressable (2.5.2)
-      public_suffix (>= 2.0.2, < 4.0)
-    capybara (2.18.0)
+    addressable (2.8.7)
+      public_suffix (>= 2.0.2, < 7.0)
+    capybara (3.35.3)
       addressable
       mini_mime (>= 0.1.3)
-      nokogiri (>= 1.3.3)
-      rack (>= 1.0.0)
-      rack-test (>= 0.5.4)
-      xpath (>= 2.0, < 4.0)
-    diff-lcs (1.3)
+      nokogiri (~> 1.8)
+      rack (>= 1.6.0)
+      rack-test (>= 0.6.3)
+      regexp_parser (>= 1.5, < 3.0)
+      xpath (~> 3.2)
+    diff-lcs (1.5.1)
     helloworld (0.0.1)
-    mini_mime (1.0.0)
-    mini_portile2 (2.3.0)
-    mustermann (1.0.2)
-    nokogiri (1.8.2)
-      mini_portile2 (~> 2.3.0)
-    public_suffix (3.0.2)
-    rack (2.0.4)
-    rack-protection (2.0.1)
+    mini_mime (1.1.2)
+    mini_portile2 (2.6.1)
+    mustermann (2.0.2)
+      ruby2_keywords (~> 0.0.1)
+    nokogiri (1.12.5)
+      mini_portile2 (~> 2.6.1)
+      racc (~> 1.4)
+    public_suffix (4.0.7)
+    racc (1.8.1)
+    rack (2.2.10)
+    rack-protection (2.2.4)
       rack
-    rack-test (0.8.3)
-      rack (>= 1.0, < 3)
-    rake (12.3.0)
-    rspec (3.7.0)
-      rspec-core (~> 3.7.0)
-      rspec-expectations (~> 3.7.0)
-      rspec-mocks (~> 3.7.0)
-    rspec-core (3.7.1)
-      rspec-support (~> 3.7.0)
-    rspec-expectations (3.7.0)
+    rack-test (2.1.0)
+      rack (>= 1.3)
+    rake (13.2.1)
+    regexp_parser (2.9.2)
+    rspec (3.13.0)
+      rspec-core (~> 3.13.0)
+      rspec-expectations (~> 3.13.0)
+      rspec-mocks (~> 3.13.0)
+    rspec-core (3.13.2)
+      rspec-support (~> 3.13.0)
+    rspec-expectations (3.13.3)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.7.0)
-    rspec-mocks (3.7.0)
+      rspec-support (~> 3.13.0)
+    rspec-mocks (3.13.2)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.7.0)
-    rspec-support (3.7.1)
-    sinatra (2.0.1)
-      mustermann (~> 1.0)
-      rack (~> 2.0)
-      rack-protection (= 2.0.1)
+      rspec-support (~> 3.13.0)
+    rspec-support (3.13.1)
+    ruby2_keywords (0.0.5)
+    sinatra (2.2.4)
+      mustermann (~> 2.0)
+      rack (~> 2.2)
+      rack-protection (= 2.2.4)
       tilt (~> 2.0)
-    tilt (2.0.8)
-    xpath (3.0.0)
+    tilt (2.4.0)
+    xpath (3.2.0)
       nokogiri (~> 1.8)
 
 PLATFORMS
@@ -61,4 +67,4 @@ RUBY VERSION
    ruby 2.5.0p0
 
 BUNDLED WITH
-   1.16.1
+   1.16.6

session1/3-challenge/1_arithmetic.rb

@@ -9,5 +9,5 @@
 # arithmetic1(-6)     # => -50
 
 def arithmetic1(n)
-
+  (n * 5) - 20
 end

session1/3-challenge/2_arithmetic.rb

@@ -9,4 +9,9 @@
 # arithmetic2(-6, -7)  # => -3.5
 
 def arithmetic2(a, b)
+  if a <= b
+    a.to_f / 2
+  else
+    b.to_f / 2
+  end
 end

session1/3-challenge/3_simple_logic.rb

@@ -8,4 +8,9 @@
 # ten_twenty(6) # => 10
 
 def ten_twenty(n)
+  if n % 2 == 0
+    10
+  else
+    20
+  end
 end

session1/3-challenge/4_logic.rb

@@ -13,6 +13,15 @@
 
 
 def grade(num_books, has_read_books)
+  base_grade = case num_books
+               when 0...10 then 'D'
+               when 10..20 then 'C'
+               else 'B'
+               end
+
+  grades = ['A', 'B', 'C', 'D']
+  grade_index = grades.index(base_grade)
+  has_read_books ? grades[grade_index - 1] : base_grade
 end
 
 

session1/3-challenge/5_string.rb

@@ -1,8 +1,9 @@
 # Given a string, replace every instance of sad to happy
-# 
+#
 # add_more_ruby("The clowns were sad.")         # => "The clowns were happy."
 # add_more_ruby("The sad dad said sad stuff.")  # => "The happy dad said happy stuff."
 # add_more_ruby("Sad times are ahead!")         # => "Happy times are ahead!"
 
 def add_more_ruby(string)
-end
+  string.gsub('sad', 'happy').gsub('Sad', 'Happy')
+end

session1/3-challenge/6_string.rb

@@ -6,5 +6,9 @@
 #
 
 def odds_and_evens(string, return_odds)
-
-end
+  if return_odds == true
+    (1..string.length-1).step(2).map { |i| string[i] }.join
+  else
+    (0..string.length-1).step(2).map { |i| string[i] }.join
+  end
+end

session1/3-challenge/7_string.rb

@@ -5,5 +5,5 @@
 # pirates_say_arrrrrrrrr("Pirates say arrrrrrrrr")        # => "arrrrrrrr"
 
 def pirates_say_arrrrrrrrr(string)
-
+  string.each_char.each_cons(2).select { |a,b| a.downcase == 'r' }.map(&:last).join
 end

session2/3-challenge/1_input_output.rb

@@ -8,6 +8,6 @@
 # "11\n7\n18\n" to standard output.
 
 def sum_difference_product
-  # your code goes here
-
-end
+  a, b = gets.split.map(&:to_i)
+  puts [a + b, a - b, a * b]
+end