''' Original After Set Sorting Sorting Char freq. b a d | a b d | a b d | 1 1 1 e f f a c e | a c e f | a c e e f f | 1 1 2 2 f e e d | d e f | d e e f | 1 2 1 c a b | a b c | a b c | 1 1 1 f a c e | a c e f | a c e f | 1 1 1 1 b e e f | b e f | b e e f | 1 2 1 d a d | a d | a d d | 1 2 c a f e | a c e f | a c e f | 1 1 1 1 a d d | a d | a d d | 1 2 a c c e d e | a c d e | a c c e e d | 1 2 2 1 b e a d | a b d e | a b d e | 1 1 1 1 f a c a d e | a c d e f | a c d e f | 1 1 1 1 1 f a d e | a d e f | a d e f | 1 1 1 1 d e c a d e | a c d e | a c d d e e | 1 1 2 2 a c e | a c e | a c e | 1 1 1 Minimum length here is 3. So all words.length >= 3 >> Words are only made up of `a-b-c-d-e-f` and I think that must be it (it was) ''' with open('words.txt', 'r') as f: words = [line.strip().lower() for line in f if line.strip()] def is_valid(word): if len(word) < 2: return False for char in word.lower(): if char not in "abcdef": return False return True valid_words = [] for word in words: if is_valid(word): valid_words.append(word) with open('valid_words.txt', 'w') as f: for word in valid_words: f.write(word + '\n') print(f"Found {len(valid_words)} valid words out of {len(words)}")