Question

the issue is I want to initialize a multiset iterator to some value, to be able to check later if there was some successful assignment to my iterator or not. Now without this initialization in some cycle of my program I get there some trash and all crashes.
In pseudocode I’d think about it like that:

multiset<whateverclassA,whateverclassB>::const_iterator init_me = NULL;
...//if succesfull, something is assigned to init_me iterator
if (init_me != NULL)
//do something

however it is not a usual pointer, so simple NULL doesn’t suffice probably.
Any help appreciated!

Answer 1

Use std::multiset::end. This is also the value that will be returned by algorithms like std::multiset::find if the value could not be found:

multiset<whateverclassA,whateverclassB>::const_iterator 
    init_me = your_multiset.end();

/* ... */

if (init_me != your_multiset.end())
    //do something