C++ can't create vector

Answer 1

Try:

std::vector<int> otherOrder;

vector is part of the std namespace. This means that whenever you use a vector in a header file, you should include the std:: prefix.

The reason that you can sometimes get away with forgetting it is that some included files may have using namespace std; in them, allowing you to leave off the prefix. However, you should avoid the using keyword in header files, for it will pollute the namespace of any files that include it.

For a more detailed explanation of the dangers of using namespace ..., see this thread.

Answer 2

Try std::vector<int>. You're supposed to use the namespace --- I'm assuming you have

using namespace std;

in the main.h someplace. There's a lot of talk on SO as to why using using is bad practice ; I'd recommend that you check it out.

Answer 3

All C++ standard library objects live in the std namespace. Try

class MyClass
{

public:
    int someint;
    std::vector<int> myOrder;
//  ^^^^^
};

Answer 4

std::vector<int> ?