i never use make_pair before but if i was correct make_pair should be have 2 parameter for it ?
make_pair(x1,x2);
but <DWORD,CouponList> will can't complete in this function in vs2017 don't know why ?
finally i fix it
Code:
m_vecCouponList.push_back(std::make_pair(it->first, it->second));