Uses the delete-expression delete ptr if T is not an array type; delete[] ptr if T is an array type (since C++17) as the deleter. Y must be a complete type. The delete expression must be well-formed, have well-defined behavior and not throw any exceptions. This constructor additionally does not participate in overload resolution if the delete expression is not well-formed. (since C++17)



따로 deleter 안 넣어줘도 알아서 동적할당된 배열 delete[]로 지워주네 ㅋㅋㅋ