add number guessing game

Author: eirinikos

README.md

@@ -6,6 +6,9 @@ Run `ruby tictactoe.rb` from your command line to enjoy a game of Tic-Tac-Toe.
 
 Play against another human or play against the computer; play on a conventional 3x3 board or play on a 4x4 board. :)
 
+####number_guess.rb
+Run `ruby number_guess.rb` to see what this one does (or, just read the comments :).
+
 ####cracklepop.rb
 Run `ruby cracklepop.rb` to see what this one does (or, just read the comments :).
 

number_guess.rb

@@ -0,0 +1,53 @@
+# determine a random number from 1-100 & let the user guess the number
+# report back whether their guess is correct, too high, or too low
+
+# if the user guesses a number they've already guessed,
+# tell them they have previously guessed this number
+
+# once they've guessed the correct number, congratulate them &
+# tell them how many guesses they took to solve the problem (minus any duplicate guesses)
+
+class Game
+  def initialize
+    @random_num = (1..100).to_a.sample
+    @all_guesses = Array.new
+  end
+
+  def initial_prompt
+    print "\nGuess the number I have chosen (it's between 1 and 100): "
+    receive_guess
+  end
+
+  def receive_guess
+    @guess = gets.chomp.to_i
+    check_guess(@guess)
+  end
+
+  def check_guess(guess)
+    if (1..100).include?(@guess.to_i)
+      if @all_guesses.include?(@guess)
+        print "\nHEY! You've already guessed that! Guess again: "
+        receive_guess
+      else
+        @all_guesses << @guess 
+      end
+      
+      if @guess == @random_num
+        print "\nCONGRATULATIONS! It only took you #{@all_guesses.count} unique guesses to guess correctly!"
+        print "\nBye now!\n\n"
+        exit(0) 
+      elsif @guess < @random_num
+        print "\nYour guess is too low. Try again: "
+        receive_guess
+      else
+        print "\nYour guess is too high. Try again: "
+        receive_guess
+      end
+    else
+      print "\nThat's not a valid choice."
+      initial_prompt
+    end
+  end
+end
+
+Game.new.initial_prompt