def count_words (text):
	text = text.lower()
	text = text.replace(",", " ")
	text = text.replace(".", " ")
	text = text.replace(":", " ")
	text = text.replace("-", " ")
	text = text.replace(";", " ")
	for n in text:
		if n.isdigit():
			text.lstrip()
		else:
			pass
	words = text.split()

	new_words = []
	for word in words:
		new_word  = ""
		if len(word) < 2:
			pass
		else:
			new_words.append(word)

	odd_words = ['и', 'в','по', 'а', 'к', 'под', 'на', 'о', 'с', 'но']
	counter = {}
	for w in new_words:
		if w in counter:
			counter[w] = counter[w] + 1
		else:
			counter[w] = 1
	for w in odd_words:
		if w in counter:
			del counter[w]
	from operator import itemgetter
	sort = sorted(counter, key=itemgetter(1), reverse=False)
	return sort

s = input()
print(count_words(s))
	

89a2e95312c25677fd4f0d7793bd51a5c3d32d9c
<mask token>

def count_words(text):
    text = text.lower()
    text = text.replace(',', ' ')
    text = text.replace('.', ' ')
    text = text.replace(':', ' ')
    text = text.replace('-', ' ')
    text = text.replace(';', ' ')
    for n in text:
        if n.isdigit():
            text.lstrip()
        else:
            pass
    words = text.split()
    new_words = []
    for word in words:
        new_word = ''
        if len(word) < 2:
            pass
        else:
            new_words.append(word)
    odd_words = ['и', 'в', 'по', 'а', 'к', 'под', 'на', 'о', 'с', 'но']
    counter = {}
    for w in new_words:
        if w in counter:
            counter[w] = counter[w] + 1
        else:
            counter[w] = 1
    for w in odd_words:
        if w in counter:
            del counter[w]
    from operator import itemgetter
    sort = sorted(counter, key=itemgetter(1), reverse=False)
    return sort


<mask token>

def count_words(text):
    text = text.lower()
    text = text.replace(',', ' ')
    text = text.replace('.', ' ')
    text = text.replace(':', ' ')
    text = text.replace('-', ' ')
    text = text.replace(';', ' ')
    for n in text:
        if n.isdigit():
            text.lstrip()
        else:
            pass
    words = text.split()
    new_words = []
    for word in words:
        new_word = ''
        if len(word) < 2:
            pass
        else:
            new_words.append(word)
    odd_words = ['и', 'в', 'по', 'а', 'к', 'под', 'на', 'о', 'с', 'но']
    counter = {}
    for w in new_words:
        if w in counter:
            counter[w] = counter[w] + 1
        else:
            counter[w] = 1
    for w in odd_words:
        if w in counter:
            del counter[w]
    from operator import itemgetter
    sort = sorted(counter, key=itemgetter(1), reverse=False)
    return sort


<mask token>
print(count_words(s))

def count_words(text):
    text = text.lower()
    text = text.replace(',', ' ')
    text = text.replace('.', ' ')
    text = text.replace(':', ' ')
    text = text.replace('-', ' ')
    text = text.replace(';', ' ')
    for n in text:
        if n.isdigit():
            text.lstrip()
        else:
            pass
    words = text.split()
    new_words = []
    for word in words:
        new_word = ''
        if len(word) < 2:
            pass
        else:
            new_words.append(word)
    odd_words = ['и', 'в', 'по', 'а', 'к', 'под', 'на', 'о', 'с', 'но']
    counter = {}
    for w in new_words:
        if w in counter:
            counter[w] = counter[w] + 1
        else:
            counter[w] = 1
    for w in odd_words:
        if w in counter:
            del counter[w]
    from operator import itemgetter
    sort = sorted(counter, key=itemgetter(1), reverse=False)
    return sort


s = input()
print(count_words(s))

def count_words (text):
	text = text.lower()
	text = text.replace(",", " ")
	text = text.replace(".", " ")
	text = text.replace(":", " ")
	text = text.replace("-", " ")
	text = text.replace(";", " ")
	for n in text:
		if n.isdigit():
			text.lstrip()
		else:
			pass
	words = text.split()

	new_words = []
	for word in words:
		new_word  = ""
		if len(word) < 2:
			pass
		else:
			new_words.append(word)

	odd_words = ['и', 'в','по', 'а', 'к', 'под', 'на', 'о', 'с', 'но']
	counter = {}
	for w in new_words:
		if w in counter:
			counter[w] = counter[w] + 1
		else:
			counter[w] = 1
	for w in odd_words:
		if w in counter:
			del counter[w]
	from operator import itemgetter
	sort = sorted(counter, key=itemgetter(1), reverse=False)
	return sort

s = input()
print(count_words(s))
	
