Class Constructor to initialize vector of vector

Question

I want initialize a vector of vector of bool inside my costructor.

This is my class:

class MyClass{
public:
    MyClass(const OtherClass&g):
        g(g), count(g.node_count(), std::vector<bool>(16))){}


private:
    const OtherClass&g;
    std::vector<std::vector<bool>>count;
};

but when I try to initialize count I obtain this error:

error: no match for call to ‘(std::vector<std::vector<bool> >) (int)’

Unrelated, try to avoid vector<bool>, it's a hybrid monster. You can use std::bitset<> instead. — vsoftco
– vsoftco, Commented Dec 6, 2016 at 14:51
strange why use a vector if you know that you need 16 bool ? and why const OtherClass& ? Trouble incoming with this design. When you give a reference of an object(A) to an other object(B) this object(A) should belong to him(B) so why const ? (maybe you don't want to modify him, so it's ok) — Stargateur
– Stargateur, Commented Dec 6, 2016 at 14:53

Valentin · Accepted Answer · 2016-12-06 14:44:09Z

3

You want to use fill constructor. If you don't use c++ 11 you need to specify the default value for elements in the vector count(g.node_count(), std::vector<bool>(16, true))

edited Dec 6, 2016 at 14:44

answered Dec 6, 2016 at 14:33

Valentin

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Comments

Danh · Accepted Answer · 2016-12-14 17:20:02Z

0

First of all I want to ask if you know that vector<bool> is a special type of vector with a bit different implementation because of optimisation, which can cause a bit different behaviour in some cases.

If you want to use it, you must pass to constructor vector<bool>(16, true) filling it with 16 true values.

edited Dec 14, 2016 at 17:20

Danh

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answered Dec 6, 2016 at 17:51

Maroš Beťko

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