def swap_case(s):
    return s.swapcase()

if __name__ == '__main__':
    s = input()
    result = swap_case(s)
    print(result)

def swap_case(s):
    new_s = ''
    for i in s:
        if i.upper() == i:
            new_s += i.lower()
        else:
            new_s += i.upper()
    return new_s

if __name__ == '__main__':
    s = input()
    result = swap_case(s)
    print(result)

LOWER_A_VALUE = ord('a')

def swap_case(s):
    return ''.join(ch.lower() if ord(ch) < LOWER_A_VALUE else ch.upper() for ch in s)

if __name__ == '__main__':
    s = input()
    result = swap_case(s)
    print(result)

def swap_case(s):
    return ''.join([c.upper() if c == c.lower() else c.lower() for c in s])

if __name__ == '__main__':
    s = input()
    result = swap_case(s)
    print(result)