或更简洁
if set(L) & set(M): # there is an intersectionelse: # no intersection
如果您确实需要
True或
False
bool(set(L) & set(M))
经过一段时间后，这似乎也是尝试的好选择
m_set=set(M)any(x in m_set for x in L)
如果M或L中的项目不可散列，则必须使用效率较低的方法，例如
any(x in M for x in L)
以下是100个商品列表的一些时间安排。在没有交集的情况下，使用集合的速度要快得多，在有交集的情况下，使用集合的速度要慢一些。
M=range(100)L=range(100,200)timeit set(L) & set(M)10000 loops, best of 3: 32.3 µs per looptimeit any(x in M for x in L)1000 loops, best of 3: 374 µs per looptimeit m_set=frozenset(M);any(x in m_set for x in L)10000 loops, best of 3: 31 µs per loopL=range(50,150)timeit set(L) & set(M)10000 loops, best of 3: 18 µs per looptimeit any(x in M for x in L)100000 loops, best of 3: 4.88 µs per looptimeit m_set=frozenset(M);any(x in m_set for x in L)100000 loops, best of 3: 9.39 µs per loop# Now for some random listsimport randomL=[random.randrange(200000) for x in xrange(1000)]M=[random.randrange(200000) for x in xrange(1000)]timeit set(L) & set(M)1000 loops, best of 3: 420 µs per looptimeit any(x in M for x in L)10 loops, best of 3: 21.2 ms per looptimeit m_set=set(M);any(x in m_set for x in L)1000 loops, best of 3: 168 µs per looptimeit m_set=frozenset(M);any(x in m_set for x in L)1000 loops, best of 3: 371 µs per loop
