dictionary - map.end() error "iterator not dereferenceable" c++ -

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//works     cout << "map[0] value " << doublestatsmap.begin()->first<< endl; //gives error cout << "map[last value " << doublestatsmap.end()->first << endl;

im trying value of last element of map. works correctly "map.begin->first" giving "map/set iterator not dereferencable" "map.end()->first". cant empty map has beginning has end. i've read says should work. suggestions appreciated!

trying end iterator causes undefined behavior.

to last item, can use std::map::rbegin().

// cout << "map[last value " << doublestatsmap.end()->first << endl; cout << "map[last value " << doublestatsmap.rbegin()->first << endl;




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