test.py

Question

def main():
    result = ""
    cards = ["2","3","5","5","J"]
    previous = cards[0]
    current = cards[1]

    i = 1
    while i < len(cards) and result == "" :

        previous = cards[i - 1]
        current = cards[i]

        if current == previous:
            result = result + current
            result = result + previous
        i = i + 1

    print(result)

main()

＃需要使用2个字符，而不是我想要["2D","3C","5H","5D","JS"]的数字列表，但我不知道该怎么做......

Answer 1

在previous = [i-1]行中，您忘了放cards[i-1]

如果你想把两位数字，但只比较你的牌数，你可以只比较字符串的第一个字符：

if current[0] == previous[0]:
    result = result + current
    result = result + previous

这打印给我5D5H

Answer 2

String对象支持索引。例如

string = 'ABC123'
string[0]   | 'A'
string[-1]  | '3'
string[0:3] | 'ABC'

因此，通过使用if current[0] == previous[0]:，您正在检查字符串的第一个值。

def main():
    result = ""
    cards = ["2D","3C","5H","5D","JS"]
    previous = cards[0]
    current = cards[1]

    i = 1
    while i < len(cards) and result == "":

        previous = cards[i-1]
        current = cards[i]

        if current[0] == previous[0]:
            result = previous + current

        i = i + 1

    print(result)

main()

Answer 3

这是一个使用itertools的更多Pythonic解决方案：

test.py

from itertools import tee

def pairwise(iterable):
    "s -> (s0,s1), (s1,s2), (s2, s3), ..."
    a, b = tee(iterable)
    next(b, None)
    return zip(a, b)

def main():
    result = ""
    cards = ["2D","3C","5H","5D","JS"]

    # Generate adjacent pairs
    for prev, curr in pairwise(cards):
      # Append `prev` to `curr` if the first character is the same.
      if prev[0] == curr[0]:
        result = curr + prev

    print(result)

if __name__ == "__main__":
    main()

函数pairwise将采用可迭代的s = ["s0", "s1", "s2", "s3"]，它可以由两个相邻的元素迭代。也就是说，你可以看看＆＃34;当前＆＃34;和＃34;下一个＆＃34;或者以前的＆＃34;和＃34;当前＆＃34;。我之所以选择prev和curr是因为next是Python中的关键字（请参阅pairwise中的实际使用情况）。

您可以执行类似

的操作

for prev, curr in pairwise(s):
  print("prev: {}, curr: {}".format(prev, curr))

这将打印：

prev: s0, curr: s1
prev: s1, curr: s2
prev: s2, curr: s3

然后，您可以使用字符串索引检查每个字符串的第一个元素。

07:35 $ python3 test.py 
5H5D

尝试使用两个字符而不仅仅是一个字符

3 个答案:

test.py