如何生成单词中低位和高位字符的所有组合？

Question

如何生成单词中低位和高位字符的所有组合？ e.g：

let sleepHoursSurveyActivity = OCKCarePlanActivity.assessment( withIdentifier: ActivityIdentifier.sleepHours.rawValue, groupIdentifier: nil, title: "Sleep Hours", text: nil, tintColor: .darkGreen, resultResettable: true, schedule: dailyScheduleRepeating(occurencesPerDay: 1), userInfo: ["ORKTask" : AssessmentTaskFactory.sleepHoursSurveyAssessmentTask()]) static func sleepHoursSurveyAssessmentTask() -> ORKTask { var steps = [ORKQuestionStep]() let question = NSLocalizedString("How many hours did you sleep?", comment: "") let textChoices = [ ORKTextChoice(text: "1-3", value: "1-3" as NSString), ORKTextChoice(text: "4-5", value: "4-5" as NSString), ORKTextChoice(text: "6-7", value: "6-7" as NSString), ORKTextChoice(text: "8", value: "8" as NSString), ORKTextChoice(text: "more than 8", value: "more than 8" as NSString) ] let questAnswerFormat: ORKTextChoiceAnswerFormat = ORKAnswerFormat.choiceAnswerFormat(with: .singleChoice, textChoices: textChoices) let sleepHoursSurvaySteps = ORKQuestionStep(identifier: "sleepHours", title: question, answer: questAnswerFormat) sleepHoursSurvaySteps.isOptional = false steps += [sleepHoursSurvaySteps] return ORKOrderedTask(identifier: "sleepHoursSurveyTask", steps: [sleepHoursSurvaySteps]) } →'abc'

['abc', 'ABC', 'Abc', 'ABc', 'aBC', 'aBc', 'abC', 'Abc']→'ab'

Answer 1

您可以通过zipping大写和小写字母以及他们的笛卡尔product来实现此目的：

import itertools

chars = "abc"
results = list(map(''.join, itertools.product(*zip(chars.upper(), chars.lower()))))

print(results)
>>>['ABC', 'ABc', 'AbC', 'Abc', 'aBC', 'aBc', 'abC', 'abc']

为了想象这是如何运作的，zip正在创造我们的3轴＆＃39;对我们来说，每个都有2个点，大写和小写字母：[('A', 'a'), ('B', 'b'), ('C', 'c')]

product取这些轴的笛卡尔积，即与其创建的单位立方体的角相对应的8个可能的离散点：

Answer 2

使用递归

def foo(word):
    if len(word) == 1:
        return [word.lower(), word.upper()]

    return [f"{j}{i}" for j in foo(word[0]) for i in foo(word[1:])]


s = "abc"
print(foo(s))

['abc', 'abC', 'aBc', 'aBC', 'Abc', 'AbC', 'ABc', 'ABC']