That's because it's not tested (at least in some languages). There are already raised issues about this below.
Didn't they say not to mutate the list?
Some of the solutions i read do this...
Why - operation is supported between these two thing? Should we regard these as two set?
@bkaes could you take a look at this?
In my opinion, "Don't mutate the origin array" this rule limited many clever solutions, so I think we dont have to follow the rule as soon as the solution is really clever 0^0
This comment is hidden because it contains spoiler information about the solution
the callback function lambda here is a little confusing, I've found an example here: https://stackoverflow.com/questions/18737863/passing-a-function-to-re-sub-in-python
Pythonic! I wrote ugly codes...
Nice solution! dict is a built-in function, so maybe d is better.
This solution is REALLY WTF!!!