Returning an empty vector of strings if key is not found

Question

I know it is a very bad idea, so other suggestions on how to do it efficiently will be well-received.

Here\'s the thing. I have map

Answer 1

I think the operator [] can help you, it will return a empty value(a empty vector here). So all you need to do is

vector returnEdges(string key) 
{
    return outgoing[key];
}