Do we need to check if an unordered_set contains an element before trying to erase it?

Question

Say I have a set:

std::unordered_set<int> mints;

Then I do:

mints.erase(foo);

But mints doesn't contain foo! Is it guaranteed that nothing bad will happen, and that erase will simply just return 0 ?

Answer 1

如果您通过用erase( const key_type& key )获得了重载的erase() ，并且该键不存在，则不会发生任何不良情况，这将是一个无操作，并且erase()将返回0 。