from sys import stdin

n, m = [int(x) for x in stdin.readline().strip().split(' ')]

n_numbers = set()
m_numbers = set()

for _ in range(n):
    n_numbers.add(int(stdin.readline().strip()))

for _ in range(m):
    m_numbers.add(int(stdin.readline().strip()))

print(len(list(m_numbers & n_numbers)))
for i in sorted(list(m_numbers & n_numbers)):
    print(i, end=' ')
print()

print(len(list(n_numbers - m_numbers)))
for i in sorted(list(n_numbers - m_numbers)):
    print(i, end=' ')
print()

print(len(list(m_numbers - n_numbers)))
for i in sorted(list(m_numbers - n_numbers)):
    print(i, end=' ')
print()