# Name: Example Solutions
# Homework 1, Exercise 2.2: rps.py

# Truth Table
# Player 1   Player 2   Result
# -------------------------------
# Rock       Rock       Tie
# Rock       Scissors   Player 1
# Rock       Paper      Player 2
# Scissors   Rock       Player 2
# Scissors   Scissors   Tie
# Scissors   Paper      Player 1
# Paper      Rock       Player 1
# Paper      Scissors   Player 2
# Paper      Paper      Tie

# Note: You could just have 10 statements in an if/elif/else structure, but
# if you look at the cases, you can simplify it down, which is what I've
# done below.

# Get the user's input
print "Please enter the players' choices (choose from rock, paper, and scissors):"
player1 = raw_input("Player 1? ")
player2 = raw_input("Player 2? ")

# Validate the input (must be one of "rock", "paper", or "scissors")
# (This could also be after all other checks, but this way you know that
# if the game is played, both inputs are valid.)
if (player1 != "rock" and player1 != "paper" and player1 != "scissors") or \
   (player2 != "rock" and player2 != "paper" and player2 != "scissors"):
    print "Invalid input.  The players must choose from 'rock', 'paper', and 'scissors'."

# If the input was valid, go ahead and continue
else:
    # It's a tie if the players picked the same value
    if player1 == player2:
        print "Tie!"
    
    # Situations where player 1 wins
    elif player1 == "rock" and player2 == "scissors" or \
       player1 == "scissors" and player2 == "paper" or \
       player1 == "paper" and player2 == "rock":
        print "Player 1 wins."

    # If it's not a tie and player 1 didn't win, then player 2 must win
    else:
        print "Player 2 wins."