Rock-Paper-Scissors Game

Question

I'm currently pretty stuck on this rock, paper, scissors program and would greatly appreciate some help. I have looked through other posts concerning rock, paper, scissors programs but I'm still stuck.

The error I'm getting currently is When I ask the user to choose 'Rock', 'Paper' or 'Scissors' it will keep asking it a couple more times and then I get an error. Also, it seems to me that a good portion of the posts I look at involve concepts that I haven't used in class, so I'm not comfortable with them.

      choices = [ 'Rock', 'Paper', 'Scissors' ]
# 1. Greetings & Rules
def showRules():
    print("\n*** Rock-Paper-Scissors ***\n")

    print("\nEach player chooses either Rock, Paper, or Scissors."
          "\nThe winner is determined by the following rules:"
          "\n   Scissors cuts Paper   ->  Scissors wins"
          "\n   Paper covers Rock     ->  Paper wins"
          "\n   Rock smashes Scissors ->  Rock wins\n")

# 2. Determine User Choice
def getUserChoice():
    usrchoice = input("\nChoose from Rock, Paper or Scissors: ").lower()
    if (usrchoice not in choices):
        usrchoice = input("\nChoose again from Rock, Paper or Scissors: ").lower()
    print('User chose:', usrchoice)
    return usrchoice

# 3. Determine Computer choice
def getComputerChoice():
    from random import randint
    randnum = randint(1, 3)
    cptrchoice = choices(randnum)
    print('Computer chose:', cptrchoice)
    return randnum

# 4. Determine Winner
def declareWinner(user, computer):
    if usrchoice == cptrchoice:
        print('TIE!!')
    elif (usrchoice == 'Scissors' and cptrchoice == 'Rock'
         or usrchoice == 'Rock' and cptrchoice == 'Paper'
         or usrchoice == 'Paper' and cptrchoice == 'Scissors'):
        print('You lose!! :(')
    else:
        print('You Win!! :)')


#5. Run program
def playGame():
    showRules()                     # Display the title and game rules
    user = getUserChoice()       # Get user selection (Rock, Paper, or Scissors)
    computer = getComputerChoice()  # Make and display computer's selection
    declareWinner(user, computer)   # decide and display winner

Answer 1

You have few problems with the code:

First is you are converting user input to lowercase but your list items are not. So the check will fail.

choices = [ 'rock', 'paper', 'scissors' ]

Second thing is you are calling choice(randnum) which will throw an error as you have to use [] to retrieve element from list.

cptrchoice = choices[randnum]

Third is what happens if you enter invalid string. You only check with if but you need while loop

while (usrchoice not in choices):
    usrchoice = getUserChoice() #input("\nChoose again from Rock, Paper or Scissors: ").lower()

Fourth is in declareWinner , your params are user and computer but then you are using usrchoice and cptrchoice in if conditions

def declareWinner(usrchoice, cptrchoice):
    if usrchoice == cptrchoice:

Try this and give it a shot