import sys

data = input()

if len(data) < 1 or len(data) > 100:
	sys.exit()

list = list(data)

for i in list:

	if i.islower():
		list[list.index(i)] = i.upper()

	elif i.isupper():
		list[list.index(i)] = i.lower()

print(''.join(list))