Looking for pair in a list of playing cards-CodePudding

So I am creating a card game in python. For the part of the game I an currently working on, I need to check an array of playing cards to see if there are any pairs. A pair is considered two cards with the same value and color. For example, king of hearts and king of diamonds are a pair, but king of hearts and king of clubs aren't.

I need to return a new list with all of the pairs removed.

Suppose we have

list = ['9♠', '5♠', 'K♢', 'A♣', 'K♣', 'K♡', '2♠', 'Q♠', 'K♠', 'Q♢', 'J♠', 'A♡', '4♣', '5♣', '7♡', 'A♠', '10♣', 'Q♡', '8♡', '9♢', '10♢', 'J♡', '10♡', 'J♣', '3♡']

The result should be:

list without pairs = ['10♣', '2♠', '3♡', '4♣', '7♡', '8♡', '9♠', '9♢', 'A♣', 'A♡', 'A♠', 'J♠', 'J♡', 'J♣', 'K♢', 'K♣', 'K♡', 'K♠', 'Q♠']

I currently have this code:

import random
result=[]

for i in range(len(l)):
    if '♣' in l[i]:
        pass
    elif '♠' in l[i]:
        pass
    elif '♡' in l[i]:
        pass
    elif '♢' in l[i]:
        pass

random.shuffle(result)
return result

CodePudding user response：

You can use below code. It is based on sorting by numbers and then compare the colors of successive cards. Comparing color is based on the ordinal logic:

def get_card(card):
    return (card[:-1], card[-1]) # save number and color


if __name__ == "__main__":
    mylist = ['9♠', '5♠', 'K♢', 'A♣', 'K♣', 'K♡', '2♠', 'Q♠', 'K♠', 'Q♢', 'J♠', 'A♡', '4♣', '5♣', '7♡', 'A♠', '10♣', 'Q♡',
            '8♡', '9♢', '10♢', 'J♡', '10♡', 'J♣', '3♡']

    # Sort the cards based on numbers
    mylist.sort(key=lambda x: x[0])
    print(mylist)

    output = []
    index = 0
    while index < len(mylist)-1:
        # Compare successive two cards

        first_card = get_card(mylist[index])
        second_card = get_card(mylist[index   1])
        print(f"Comparing {first_card} and {second_card} -- {ord(first_card[1])}   {ord(second_card[1])} = {ord(first_card[1])   ord(second_card[1])}")
        # check the number
        if (first_card[0] == second_card[0]):
            # check the color
            ord_val = ord(first_card[1])   ord(second_card[1])
            if (first_card[1] == second_card [1] or ord_val % 10 == 1 ):
                # same card, skip this card
                index  = 1
            else:
                # add card to output, dont skip next card
                output.append(mylist[index])
                print("\tAdding card")
        else:
            output.append(mylist[index])
            print("\tAdding card")
        index  = 1
    print(output)

Logic:

Use ordinal values to compare colors. Sum of ordinals of same colors(according to color symbol in your problem statement) are equal and last digit is 1. Ord values:

"""
♠: 9824   -   black - spade
♣: 9827   -   black - club
♡: 9825   -   red - heart
♢: 9826   -   red - diamond
"""
Spade   club = 9824   9827 = 19651
heart   diamond = 9825   9826 = 19651

Output:

['10♣', '2♠', '3♡', '4♣', '7♡', '8♡', '9♠', '9♢', 'A♣', 'A♡', 'A♠', 'J♠', 'J♡', 'J♣', 'K♢', 'K♣', 'K♡', 'K♠', 'Q♠']

CodePudding user response：

cards_list = [
    "9♠",
    "5♠",
    "K♢",
    "A♣",
    "K♣",
    "K♡",
    "2♠",
    "Q♠",
    "K♠",
    "Q♢",
    "J♠",
    "A♡",
    "4♣",
    "5♣",
    "7♡",
    "A♠",
    "10♣",
    "Q♡",
    "8♡",
    "9♢",
    "10♢",
    "J♡",
    "10♡",
    "J♣",
    "3♡",
]    

SAME_COLORS = {"♢": "♡", "♡": "♢", "♠": "♣", "♣": "♠"}
    
list_without_pairs = []
for card in cards_list:
    if card[:-1]   SAME_COLORS[card[-1]] in cards_list:
        continue
    else:
        list_without_pairs.append(card)

print(list_without_pairs)

Output:

['9♠', '2♠', 'Q♠', 'A♡', '4♣', '7♡', '10♣', '8♡', '9♢', 'J♡', '3♡']

This work exactly the same but could be a little bit more confuse:

list_without_pairs = [card for card in cards_list if card[:-1]   SAME_COLORS[card[-1]] not in cards_list]