merge two containers of same type [duplicate]

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• std::merge merging two std::vector coredump 4 answers

I want to merge two containers of the same type. this is the structure of the classes. im getting the following error: /cygdrive/C/Users/USER/AppData/Roaming/NetBeans/8.1/bin/nativeexecution/dorun.sh: line 33: 4400 Segmentation fault (core dumped) sh "${SHFILE}" class Customer { int id; // customer id string name; // name };

class Purchase {
    string n; // name of product
    double up; // unit price
    int c;
};

class Order {
    Customer c;
    vector<Purchase> p;
};

...
...
...
                         //main
list<Orderer> mylist{};
vector<Order>myvec{};
vector<Order>mergedvec{};
merge(mylist.begin(),mylist.end(),myvec.begin(),myvec.end(),mergedvec.begin());