def remove_least_frequent_chars(s):if not s:return "empty"# 统计每个字符的频率freq = {}for char in s:freq[char] = freq.get(char, 0) + 1if not freq:return "empty"# 找出最小的频率min_freq = min(freq.values)# 收集所有出现次数等于最小频率的字符chars_to_remove = [char for char, count in freq.items if count == min_freq]# 构建结果字符串，跳过待删除的字符result = for char in s:if char not in chars_to_remove:result.append(char)# 处理空字符串的情况if not result:return "empty"else:return ''.join(result)# 读取输入input_str = input.strip# 输出结果print(remove_least_frequent_chars(input_str))输入处理：读取输入的字符串并去除首尾空格。频率统计：使用字典freq统计字符串中每个字符的出现次数。最小频率确定：通过min(freq.values)找到字符的最小出现次数。待删除字符收集：列表推导式收集所有出现次数等于最小频率的字符。结果字符串构建：遍历原字符串，跳过待删除字符，构建结果列表。空字符串处理：检查结果列表是否为空，若为空则返回"empty"，否则返回拼接后的字符串。摘要：def remove_least_frequent_chars(s):if not s:return "empty"# 统计每个字符的频率freq = {}for char in s:freq[char] = freq.get(char, 0) + 1if n
来源：自然教育
