如何仅用基础语句找出扑克牌牌面字符串中的最大牌

Got it, let's tackle this problem! The core issue here is that Python's built-in max() function uses ASCII character values to determine "largeness"—which doesn't align with poker card hierarchy. For example, 'T' has a higher ASCII value than 'K', so max('28TKQ') incorrectly returns 'T' instead of 'K'.

We need to implement custom logic that follows the order 2 < 3 < 4 < ... < 9 < T < J < Q < K < A, using only if statements, for/while loops as requested.

Solution 1: Using a For Loop #

First, we'll define a string that represents the correct rank order. Each character's position in this string corresponds to its strength (higher index = stronger card). Then we'll iterate through the hand, keeping track of the strongest card we've seen so far.

def get_highest_card(hand):
    # Define the official poker rank order
    rank_hierarchy = '23456789TJQKA'
    # Start with the first card as our initial maximum
    highest = hand[0]
    
    # Loop through every remaining card in the hand
    for card in hand[1:]:
        # Compare the positions of the current card and our current highest
        if rank_hierarchy.index(card) > rank_hierarchy.index(highest):
            # Update highest if the current card is stronger
            highest = card
    return highest

# Test with your examples
print(get_highest_card('43TKQ'))  # Output: K
print(get_highest_card('28TKQ'))  # Output: K
print(get_highest_card('768TA'))  # Output: A
print(get_highest_card('2TJ67'))  # Output: J

Solution 2: Using a While Loop #

If you prefer a while loop instead, here's an equivalent implementation:

def get_highest_card_while(hand):
    rank_hierarchy = '23456789TJQKA'
    highest = hand[0]
    current_index = 1
    
    while current_index < len(hand):
        current_card = hand[current_index]
        if rank_hierarchy.index(current_card) > rank_hierarchy.index(highest):
            highest = current_card
        current_index += 1
    return highest

# Test the while loop version
print(get_highest_card_while('2TJ67'))  # Output: J

How This Works #

• The rank_hierarchy string acts as a reference: when we call rank_hierarchy.index(card), we get a numerical value that represents the card's strength. For example, rank_hierarchy.index('T') returns 8, rank_hierarchy.index('K') returns 11—so we know K is stronger.
• We start with the first card as our baseline "highest" card, then check every other card against it. If a card has a higher index in the hierarchy, it becomes the new highest.

This approach strictly follows your requirements: no fancy built-in functions beyond what's necessary, just loops and conditionals.

内容的提问来源于stack exchange，提问作者Peri