STL question: vector size (2 dimension)

This is a discussion on STL question: vector size (2 dimension) within the C++ Programming forums, part of the General Programming Boards category; I have a vector < vector<int> > TwoDim; What does TwoDim.size() give me? Is it (x*y), assuming x = rows, ...

  1. #1
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    STL question: vector size (2 dimension)

    I have a

    vector < vector<int> > TwoDim;


    What does TwoDim.size() give me? Is it (x*y), assuming x = rows, y = columns in the sense of an array?

    How do I get the size of x?
    How do I get the size of y?


    Thanks,
    codeguy

  2. #2
    C++まいる!Cをこわせ! Elysia's Avatar
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    It gives the number of vector<int> in your vector (aka, the size of x).
    vector[n].size() gives the size of your y size.
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    Quote Originally Posted by Elysia View Post
    It gives the number of vector<int> in your vector (aka, the size of x).
    vector[n].size() gives the size of your y size.
    And it's worth noting that vector[0].size() may well be a completely different number than vector[1].size() for example.

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    Which is why Boost.MultiArray is a better choice for most applications than jagged vectors.
    All the buzzt!
    CornedBee

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