题解 | #删除字符串中出现次数最少的字符#

# 删除字符串出现次数最少的字符

input_str = input()

def letter_idea(raw_str):
    """方法1，利用全部字母遍历（在输入不出现英文字母以外的情况下有效）"""
    letters = [item for item in 'abcdefghijklmnopqrstuvwxyz']

    detail = dict()

    for letter in letters:
        num = raw_str.count(letter)
        if num == 0:
            pass
        elif num in detail.keys():
            detail[num].append(letter)
        else:
            detail[num] = [letter]

    # 所有字符出现次数全部相等，则打印原始字符串
    if len(detail) == 1:
        print(raw_str)
    else:
        min_num = min(detail.keys())
        for i in detail[min_num]:
            raw_str = raw_str.replace(i, '')
        print(raw_str)

def general_idea(raw_str):
    """方法2，通用方法"""
    detail, res = dict(), str()
    # 数据收集
    for s in raw_str:
        if s not in detail:
            detail[s] = 1
        else:
            detail[s] += 1
    min_num = min(detail.values())
    # 结果处理   
    if len(set(detail.values())) == 1:
        print(raw_str)
    else:
        for s in raw_str:
            if detail[s] != min_num:
                res += s
    # print(detail)
    print(res)


if __name__ == '__main__':
    letter_idea(input_str)
    general_idea(input_str)