求覆盖最短字符串

# coding=utf-8
import sys


def lists_combination(lists, code=''):
    '''输入多个列表组成的列表, 输出其中每个列表所有元素可能的所有排列组合
    code用于分隔每个元素'''
    try:
        import reduce
    except:
        from functools import reduce

        def myfunc(list1, list2):
            return [str(i) + ',' + str(j) for i in list1 for j in list2]
    return reduce(myfunc, lists)


def solution(long_string, alphabet):
    # 将所需查找字符分隔，放入alphaNeedFind列表中
    alphaNeedFind = []
    strFindPlaceGroup = []
    for temp in alphabet:
        alphaNeedFind.append(temp)
        strFindPlaceGroup.append([])

    # 将查找字符串分割并分别将各所需查找字符放入该分类组中，只以在原字符串位置表示
    place = 0
    for temp in long_string:
        for alphaindex in range(len(alphaNeedFind)):
            if alphaNeedFind[alphaindex] == temp:
                strFindPlaceGroup[alphaindex].append(place)
        place += 1

    # 利用reduce函数将数组位置标识序号排序
    groupsList = lists_combination(strFindPlaceGroup)

    # 将字符串数组分成数字列表
    list = []
    i = 0
    for group in groupsList:
        list.append([])
        for num in group.split(','):
            list[i].append(int(num))
        i += 1

    # 对所有组合计算最短子字符串及长度
    finalList = [0, 0]  # 保存最短子字符串开头末尾序号
    MinDistance = None  # 保存最短子字符串长度
    for x in list:
        if MinDistance is None:
            MinDistance = max(x) - min(x)
            finalList[0] = min(x)
            finalList[1] = max(x)
        if max(x) - min(x) < MinDistance:
            MinDistance = max(x) - min(x)
            finalList[0] = min(x)
            finalList[1] = max(x)
    return long_string[finalList[0]:finalList[1] + 1]


if __name__ == "__main__":
    # 读取第一行的n
    long_string = 'eeaaccebce-abc'
    alphabet = 'abc'
    print(solution(long_string, alphabet))