HW.字符串排序

不用排序， 26次循环+双指针即可

while True:
    try:
        string = list(input())
        result = list(string)
        index = 0
        for i in range(26):
            char = chr (97 + i)

            for i in range(len(string)):
                if string[i].lower() == char:
                    while(not result[index].isalpha()):
                        index += 1
                    result[index] = string[i]
                    index += 1
        print("".join(result))
    except:
        break