import operator 

def frequencies(ciphertext):
	freq=[0]*26
	for i in ciphertext:
		int_letter = ord(i) - ord('a')
		freq[int_letter]+=1
	return freq



def main():

	ciphertextInput = input("input ciphertext ")
	ciphertextInput = ciphertextInput.replace(" ", "")
	ciphertextInput = ciphertextInput.replace("\t", "")
	ciphertextInput = ciphertextInput.replace(",", "")
	ciphertextInput = ciphertextInput.replace(";", "")
	ciphertextInput = ciphertextInput.replace("!", "")
	ciphertextInput = ciphertextInput.replace(":", "")
	ciphertextInputNoSpaces = ciphertextInput.replace(".", "")	
	print("after removing all whitespaces and punctuations")
	print(ciphertextInputNoSpaces)
	ciphertext = ciphertextInputNoSpaces.lower()
	print("after transferring to lowercase letters only")
	print(ciphertext)
	cipher_length = len(ciphertext)
	print("cipher length is ")
	print(cipher_length)

	freq = frequencies(ciphertext)
	print("frequencies are ")

	for i in range(26):
		print((chr)((ord)('a')+i), freq[i])
	
	#Creatinga dictionary, key - letter, value - frequency
	dict={}
	for i in range(26):
		next_char=(chr)((ord)('a')+i)
		dict.update({next_char:freq[i]})
	
	#sorting dictionary by frequencies (values) 
	s_dict=sorted(dict.items(),key=operator.itemgetter(1),reverse=True)
	#printing sorted dictinary
	print("Sorted by frequencies")
	for i in s_dict:
		print(i)
	#if you would like to print keys (letters) only:
	print("Printing letters only in decreasing order of frequencies")
	for i in s_dict:
		print(i[0])

main()