删除元素 | HJ23 删除字符串中出现次数最少的字符

while True:
    try:
        s = input()
        r = {}
        for i, ch in enumerate(s):
            r.setdefault(ch, 0)
            r[ch] += 1
        s_r = dict(sorted(r.items(), key=lambda x:x[1]))
        min_f = list(s_r.values())[0]
        d = [k for k,v in s_r.items() if v==min_f]
        # 法1：不用删除的元素加列表
        # res = []
        # for i in range(len(s)):
        #     if s[i] not in d:
        #         res.append(s[i])
        # print(''.join(res))

        # 法2：要删除的元素用replace
        for ch in d:
            s = s.replace(ch, '')
        print(s)

    except:
        break

用时：20min