stl vector and c++: how to .resize without a default constructor?

c++ stl constructor vector default
conejoroy picture conejoroy · Nov 6, 2009 · Viewed 12.6k times · Source

How do I tell STL, specifically for the method resize() in vector, to initialize objects with a constructor other than default, and with which parameters?

For example:

class something {
    int a;
    something (int value);
}

std::vector<something> many_things;

many_things.resize (20);

More generally, how do I force STL to use my constructor when it needs to create objects, and pass parameters to that constructor?

In my case adding a default constructor is not an option, and I'd prefer not to use an array of pointers to solve the problem.

Answer

MSalters picture MSalters · Nov 6, 2009

Use the 2-argument overload: many_things.resize(20, something(5));

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