方法1

while True:
    try:
        s = input()
        dic = {}
        for c in s:
            dic[c] = dic.get(c, 0) + 1
        min_freq = min(dic.values())
        res = "".join([c for c in s if dic[c] != min_freq])
        print(res)
    except:
        break

方法2

import sys


def remove_min_freq_chars(input_string):
    char_list = list(input_string)
    unique_chars = set(char_list)
    char_freq = {char: char_list.count(char) for char in unique_chars}

    min_freq = min(char_freq.values())
    min_freq_chars = [char for char, freq in char_freq.items() if freq == min_freq]

    # 构建一个新字符串,排除出现次数最少的字符
    new_string = ''.join([char for char in char_list if char not in min_freq_chars])
    return new_string


for line in sys.stdin:
    input_line = line.strip()
    print(remove_min_freq_chars(input_line))