2D vectors array.......

Hello everyone,
I need to make a constructor that initialize a 2d vector array by zeros or nulls......
how can i do that ._.
tried nested loops like in 2d arrays but failed
should i use push_back?or is there a way i can do this without it?

What have you tried?

Soma

Hello, as phantomotap says: tried anything? Show the code.

std::vector can be initialized just when you are creating it, like this:

Code:

---

//Creates 2D vector of size 10 and the 0 in the line below defines the default size.
std::vector<std::vector <int>> Storage(10, std::vector<int>(10, 0));

---

If you define a vector like this (with no default value):
std::vector<std::vector <int>> Storage(10, std::vector<int>(10));
Then initialize it through a loop with another inner loop:

Code:

---

int initvalue = 0;
        for(int i = 0; i < 10; i++)
        {
                for(int ii =0; ii < 10; ii++)
                {
                        Storage[ii][i] = initvalue;       
                }
        }

---

Is this all you are trying to do? You can use push.back if you want.
Or are you trying to create a 2D vector by yourself, something along these lines:

Code:

---

class Vec2D
{
    private:
      int v[2];
    public:
      Vec2D(int x, int y);
      //etc...
}

---

thx alot on the replies
this is the last thing i did and it doesn't show any errors anymore but i don't know is this even correct or not -_-" "new to programming"

Code:

---

protected:
        char w;
        int x,y;
        int i,j;
        vector<vector<char> > Vec(int i, vector<char>(int i,int j));
public:
        rand_m_tst()
        {
                w='$';
                x=0;
                y=0;
                i=20;
                j=0;
                vector<vector<char>> Vec(i,vector<char>(i,j));
                for(int f=0;f<20;f++)
                {
                        for(int j=0;j<20;j++)
                                Vec[f][j]=NULL;
                }
        };

---

the 2d vector in protected area is useless now right? -_-"