fix formatting & ads.txt

_drafts/errorchecking.md

@@ -1,3 +1,22 @@
 ## Exercise
 
+Given this solution to Exercise 9, modify it to one level of user feedback: if the user does not enter a number between 1 and 9, tell them. Don't count this guess against the user when counting the number of guesses they used.
+
+```
+import random
+
+number = random.randint(1, 9)
+number_of_guesses = 0
+while True:
+	guess = int(input("Guess a number between 1 and 9: "))
+	number_of_guesses += 1
+	if guess == number:
+		break
+print(f"You needed {number_of_guesses} to guess the number {number}")
+```
+
+
+## Discussion
+
 error checking on inputs
+can use exercise8 as an example to walk through, since there are a lot of potential error checks

_posts/2014-04-10-09-guessing-game-one-solutions.md

@@ -6,7 +6,7 @@ categories: [solution]
 
 {% include solution_header.md number=page.number %}
 
-Generate a random number between 1 and 9 (including 1 and 9). Ask the user to guess the number, then tell them whether they guessed too low, too high, or exactly right. (_Hint: remember to use the user input lessons from the very [first exercise]({% post_url 2014-01-29-01-character-input %}_)
+Generate a random number between 1 and 9 (including 1 and 9). Ask the user to guess the number, then tell them whether they guessed too low, too high, or exactly right. (_Hint: remember to use the user input lessons from the very [first exercise]({% post_url 2014-01-29-01-character-input %})_).
 
 Extras: 
 

ads.txt

@@ -0,0 +1 @@
+google.com, pub-6567168629713427, DIRECT, f08c47fec0942fa0