std::map< int, std::set<int> > wtf;
std::set< int > a = wtf[24];
printf("%d\n", a.find(5) != a.end());
a.insert(5);
printf("%d\n", a.find(5) != a.end());
std::set< int > b = wtf[24];
printf("%d\n", b.find(5) != b.end());

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