prog.cpp: In function ‘int main()’:
prog.cpp:31:10: error: use of deleted function ‘constexpr A<int>& A<int>::operator=(const A<int>&)’
aob2=aob1;
^~~~
prog.cpp:7:7: note: ‘constexpr A<int>& A<int>::operator=(const A<int>&)’ is implicitly declared as deleted because ‘A<int>’ declares a move constructor or move assignment operator
class A {
^