Merge pull request #59 from rjnienaber/add_91_train_in_ruby

add 91 train in ruby

91 Train/ruby/train.rb

@@ -0,0 +1,58 @@
+def intro
+  puts "                                 TRAIN
+               CREATIVE COMPUTING  MORRISTOWN, NEW JERSEY
+
+
+
+TIME - SPEED DISTANCE EXERCISE
+
+"
+end
+
+def get_user_guess
+  while true
+    begin
+      number = Float(gets.chomp)
+      return number
+    rescue ArgumentError
+      # Ignored
+    end
+
+    puts "!NUMBER EXPECTED - RETRY INPUT LINE"
+    print "? "
+  end
+end
+
+def main
+  intro
+
+  loop do
+    car_speed = (Random.rand * 25 + 40).to_i
+    car_time = (Random.rand * 15 + 5).to_i
+    train_speed = (Random.rand * 19 + 20).to_i
+
+    print " A CAR TRAVELING #{car_speed} MPH CAN MAKE A CERTAIN TRIP IN
+ #{car_time} HOURS LESS THAN A TRAIN TRAVELING AT #{train_speed} MPH.
+HOW LONG DOES THE TRIP TAKE BY CAR? "
+    guess = get_user_guess
+
+    answer = ((car_time * train_speed) / (car_speed - train_speed).to_f).round(5)
+    delta = (((answer - guess) * 100 / guess) + 0.5).abs.to_i
+
+    if delta > 5
+      puts "SORRY.  YOU WERE OFF BY #{delta} PERCENT."
+    else
+      puts "GOOD! ANSWER WITHIN #{delta} PERCENT."
+    end
+
+    print "CORRECT ANSWER IS #{answer == answer.to_i ? answer.to_i : answer} HOURS.
+
+ANOTHER PROBLEM (YES OR NO)? "
+    option = (gets || '').chomp.upcase
+    break unless option == 'YES'
+  end
+end
+
+trap "SIGINT" do puts; exit 130 end
+
+main