I frequently use vectors instead of arrays if I don't know what size it'll be or if I want the user to enter in the size. My question though is what do people usually do when you want to have a two or more dimensional array that you don't know what the size will be until run time?
I've been using vector<vector<blah>> but this is kind of annoying and I was wondering if there was a better/easier way.
>>I've been using vector<vector<blah>> but this is kind of annoying and I was wondering if there was a better/easier way.
Write a vector of vectors once and throw it in a matrix class, then use that class when you need a 2d vector :-)
*Cela*
So obvious, why didn't I think of that?! Thanks!
Actually, one more question about this. Would it be possible to access data directly using []'s? I know how to overload the index operators for something like this:
But I'm not sure how if even possible to overload something to get this:Code:myContainer[x];
Or am I stuck having to do something like this for my matrix:Code:myContainer[x][y];
Code:myMatrix.returnValue(x,y);
>>Would it be possible to access data directly using []'s?
Consider two classes, a matrix class and an array class. Use the array class with an overloaded [] operator and use that as a return value for the overloaded matrix [] operator :-)
Then you can access it like thisCode:template<typename T> class matrix { public: class array { public: T& operator[](int index); const T& operator[](int index) const; ... }; array operator[](int index); const array operator(int index) const; ... };
Code:matrix<int> a(5,10); ... cout<< a[i][j] <<endl;
*Cela*
Nice! Thanks, thats a useful trick to know!
