python - 在字典中迭代..(双重迭代)python

Question

我有一本字典

example: A = {1:'one',2:'two' , 3: 'three}

所以我想要的基本上就像一个 2 for 循环之类的东西..这样我就可以获得以下订单..

# 1 2
# 1 3
# 2 3
... and so on if more elements are there

所以基本上是 o(n2) 操作..我们有一个循环和一个循环我们如何在 python 字典中实现这一点。我很难弄清楚..

for key in A.keys():
      # how do i Access all the other keys.. 
           # do something

谢谢

Answer 1

>>> import itertools as it
>>> A = {1:'one', 2:'two', 3: 'three'}
>>> list(it.combinations(A.keys(), 2))
[(1, 2), (1, 3), (2, 3)]