current = [[int(x) - 1 for x in input().split()[:-1]] for _ in range(3)]
wanted = [[int(x) - 1 for x in input().split()[:-1]] for _ in range(3)]

N = max(max(t) for t in current) + 1

pos = [-1] * N
for t in range(3):
    for d in current[t]:
        pos[d] = t

wantedpos = [-1] * N
for t in range(3):
    for d in wanted[t]:
        wantedpos[d] = t

other = [
    [-1, 2, 1],
    [2, -1, 0],
    [1, 0, -1],
]

moves = []


def move(d, to):
    if pos[d] == to:
        return
    # print(f"move {d+1} to tower {to}")
    for e in range(d - 1, -1, -1):
        move(e, other[pos[d]][to])
    moves.append((pos[d], to))
    pos[d] = to


for d in range(N - 1, -1, -1):
    # print("doing", d + 1)
    move(d, wantedpos[d])

print(len(moves))
for f, t in moves:
    print(f + 1, t + 1)