main() { assert 0 | 0 == 0 assert 0 | 1 == 1 assert 1 | 0 == 1 assert 1 | 1 == 1 assert 1 | 2 == 3 assert 1 | 3 == 3 assert 2 | 0 == 2 assert 2 | 1 == 3 assert 2 | 2 == 2 assert 2 | 3 == 3 assert 3 | 0 == 3 assert 3 | 1 == 3 assert 3 | 2 == 3 assert 3 | 3 == 3 }