x = input()

l = len(x)

list = list(x)

new_list = []

for i in range(0,l):
    if ord(list[i]) >= 97:
        list[i] = chr( ord(list[i]) - 32 )
        new_list.extend(list[i])
    
    else:
        list[i] = chr( ord(list[i]) + 32 )
        new_list.extend(list[i])

password = "".join(new_list)
print(password)