diff --git a/lm3226/assignment8.py b/lm3226/assignment8.py
index b870777..54205d9 100644
--- a/lm3226/assignment8.py
+++ b/lm3226/assignment8.py
@@ -22,38 +22,42 @@ def validate_denominations_input(denominations):
             raise InvalidUserInputException("Invalid input.")
 
 def main():
-    while True:
-        try:
-            user_input = input('''Suppose that you want to invest $1000.
-            You can purchase it in $1, $10, $100, $1000 denominations. Please
-            enter a list of denominations without dollar sign that you want to
-            purchase and separate each denomination by a comma,
-            such as 1,10,100,1000: '''
-            )
-            input_denominations = np.fromstring(user_input, dtype=int, sep=',')
-            validate_denominations_input(input_denominations)
-        except (ValueError, InvalidUserInputException) as e:
-            print('Invalid input. Please try again: ')
-            continue
-        else:
-            while True:
-                try:
-                    user_num_input = input('Choose the number of times you want to invest: ')
-                    user_num_trials = int(user_num_input)
-                    if user_num_trials <= 0:
-                        raise InvalidUserInputException
-                except (ValueError, InvalidUserInputException) as e:
-                    print('Invalid input. Please try again: ')
-                    continue
-                else:
-                    user_invsetment = daily_investment_return(input_denominations, user_num_trials)
-                    user_invsetment.generate_results()
+    try:
+        while True:
+            try:
+                user_input = input('''Suppose that you want to invest $1000.
+                You can purchase it in $1, $10, $100, $1000 denominations.
+                Please enter a list of denominations without dollar sign that
+                you want to purchase and separate each denomination by a comma,
+                such as 1,10,100,1000: '''
+                )
+                input_denominations = np.fromstring(user_input, dtype=int, sep=',')
+                validate_denominations_input(input_denominations)
+            except (ValueError, InvalidUserInputException) as e:
+                print('Invalid input. Please try again: ')
+                continue
+            else:
+                while True:
+                    try:
+                        user_num_input = input('Choose the number of times you want to invest: ')
+                        user_num_trials = int(user_num_input)
+                        if user_num_trials <= 0:
+                            raise InvalidUserInputException
+                    except (ValueError, InvalidUserInputException) as e:
+                        print('Invalid input. Please try again: ')
+                        continue
+                    else:
+                        user_invsetment = daily_investment_return(input_denominations, user_num_trials)
+                        user_invsetment.generate_results()
 
-                    print('Now generating example results with denominations of [1,10,100,1000] and 10000 trials')
-                    example_investment = daily_investment_return([1,10,100,1000], 1000)
-                    example_investment.generate_results()
-                    break
-            break
+                        print('Now generating example results with denominations of [1,10,100,1000] and 10000 trials')
+                        example_investment = daily_investment_return([1,10,100,1000], 1000)
+                        example_investment.generate_results()
+                        break
+                break
+
+    except (KeyboardInterrupt, EOFError) as e:
+        sys.exit(0)
 
 if __name__ == '__main__':
     main()
diff --git a/lm3226/daily_investment_return.py b/lm3226/daily_investment_return.py
index a5d6c62..e49252c 100644
--- a/lm3226/daily_investment_return.py
+++ b/lm3226/daily_investment_return.py
@@ -74,7 +74,7 @@ def generate_histograms(self, trials):
             self.make_denomination_histogram(trials[i], self.denominations[i])
 
     def write_results_to_file(self, trials):
-        #Write mean as well as standard deviation to a file and save it into text
+        #Write mean as well as standard deviation to a file and save it into txt
         f = open('results.txt', 'w')
         for i in range(0, len(self.denominations)):
             denomination = self.denominations[i]