Code Explainer

Complete Deck Checker in Python

The `is_complete_deck` function checks if a list of playing cards forms a complete standard deck of 52 cards. It utilizes Python sets for efficient comparison and clarity through comprehensions to verify deck completeness.

Prompt

def is_complete_deck(cards):
    # Define the full set of cards
    suits = ["Spades", "Hearts", "Clubs", "Diamonds"]
    ranks = ["Ace", "2", "3", "4", "5", "6", "7", "8", "9", "10", "Jack", "Queen", "King"]
    
    full_deck = {f"{rank} of {suit}" for suit in suits for rank in ranks}
    
    # Create a set to track seen cards
    seen_cards = set(cards)
    
    # Check if the seen cards exactly match the full deck
    if seen_cards == full_deck:
        return "YES"
    else:
        return "NO"


cards = [input().strip() for _ in range(52)]


print(is_complete_deck(cards))

Answer

Code Explanation of `is_complete_deck` Function

The provided code snippet defines a Python function that checks whether a set of playing cards constitutes a complete deck. Below is a detailed breakdown of the code, its components, and underlying concepts.

Code Breakdown

Function Definition

def is_complete_deck(cards):

Function Name: is_complete_deck
Parameter: cards, which is expected to be a list containing card representations (e.g., "Ace of Spades").
This function will return a string indicating whether the given list of cards is a complete deck.

Defining the Full Deck

suits = ["Spades", "Hearts", "Clubs", "Diamonds"]
ranks = ["Ace", "2", "3", "4", "5", "6", "7", "8", "9", "10", "Jack", "Queen", "King"]
    
full_deck = {f"{rank} of {suit}" for suit in suits for rank in ranks}

Suits and Ranks: Two lists are defined to represent all possible suits and ranks in a standard deck of cards.
Set Comprehension: full_deck is created using set comprehension. This constructs a set containing every combination of ranks and suits:
- f"{rank} of {suit}" formats strings to represent each card, such as "Ace of Spades".

Creating Seen Cards Set

seen_cards = set(cards)

Conversion to Set: The input list cards is converted into a set named seen_cards. This allows for O(1) average time complexity for membership checks and ensures uniqueness, eliminating any duplicate entries.

Comparison with Full Deck

if seen_cards == full_deck:
    return "YES"
else:
    return "NO"

Equality Check: The function checks if seen_cards is equal to full_deck. If they are identical, this means every card in a complete deck is present in the input and returns "YES".
If they are not equal, it returns "NO", indicating that the input does not represent a complete deck.

Input Reading and Function Call

cards = [input().strip() for _ in range(52)]
print(is_complete_deck(cards))

Input Collection: A list comprehension is used to read exactly 52 input lines (representing cards) from the user, stripping any unnecessary whitespace.
Function Execution: The is_complete_deck function is called with the collected cards, and the result is printed.

Key Concepts Explained

Sets

Sets in Python: Sets are unordered collections of unique elements. Operations such as union, intersection, and difference can be performed efficiently.

Comprehensions

Set Comprehensions: This is a concise way to create sets using a single line of code, merging loops and conditions directly into their construction.

Additional Example

To illustrate the functionality, consider the following alternative example:

cards_example = [
    "Ace of Spades", "2 of Spades", "3 of Spades", ..., "King of Diamonds"  # All 52 cards
]
print(is_complete_deck(cards_example))  # Output: "YES"

In this case, providing a well-formed list containing every card in the deck results in a confirmation of completeness.

Conclusion

The is_complete_deck function efficiently verifies if a provided list of cards represents a complete standard deck. By utilizing sets for optimal comparisons and comprehensions for clean set construction, this code succinctly embodies best practices in Python programming. For those interested in deepening their knowledge of data structures and Python programming, courses available on the Enterprise DNA platform may offer valuable insights.

Description

The is_complete_deck function checks if a list of playing cards forms a complete standard deck of 52 cards. It utilizes Python sets for efficient comparison and clarity through comprehensions to verify deck completeness.