Cows and Bulls

This is a logic puzzle game. The goal is to guess a 3-digit number in the least number of attempts. Alexa generates a 3-digit number with unique digits to begin. The user attempts to guess a 3-digit number randomly and then Alexa provides clues in Cows and Bulls notation. For instance, if the original number is 123 and user guesses 325 - Alexa will tell the user that they have 1 bull (for digit 2 and it's accurate position) and 1 cow (for digit 3, without accurate position).

Please read this wiki page for a detailed description: https://en.wikipedia.org/wiki/Bulls_and_Cows

More detailed instructions below on using the skills:

Step 1: Start the game by prompting Alexa
You: Alexa, open cows bulls
Alexa: Welcome to Cows and Bulls number guessing game. Try to guess a three digit number in lowest number of attempts. Do you want to start?

Step 2: Say yes to start the game
You: Yes
Alexa: Great! Try saying a three digit number to start the game.

Step 3: Start guessing the number. say something on the lines of: 'could it be four nine five' (Note: these digits should be unique)
You: one two three
Alexa: You have 0 bulls and 0 cows. This is attempt number 1
You: four five six
Alexa: You have 1 bull and 0 cows. This is attempt number 2
You: seven nine eight
Alexa: You have 2 bulls and 0 cows. This is attempt number 12
You: seven nine six
Alexa: 796 is correct! Congratulations! Would you like to play a new game? It'll be fun to beat your number of attempts!

You can continue till you answer correctly, or end the game by saying stop, or play another game to beat your number of attempts!