def main():
    global mapping
    N, M = map(int, input().split())

    mapping = [[False]*N for n in range(N)]
    for m in range(M):
        a, b = map(int, input().split())
        mapping[a][b] = True
        mapping[b][a] = True

    # print(mapping)

    count = 0
    for c in itertools.combinations(range(N), 4):
        if check(c):
            print(c)
            count += 1

    print(count)

def check(p):
    stack = [(p[0], 1)]
    count = 0
    while len(stack) != 0:
        now, num = stack.pop()
        for i in range(4):
            if connected(now, p[i]):
                if num + 1 == 4:
                    count += 1
                else:
                    stack.append((p[i], num + 1))
    if count == 1:
        return True
    else:
        return False


def connected(x,y):
    if mapping[x][y] or mapping[y][x]:
        return True
    else:
        return False


if __name__ == "__main__":  # {{{
    try:
        import test
        test.test()
    except:
        main()  # }}}