Store pointer to 2d array [duplicate]

Question

So I have a private member in the class Map:

char **_map;

I then try to initialize the pointer array to a two dimensional char array like this:

std::vector<std::string> contents = StringUtils::split(_mapInfo.getContents(), ' ');
const int x = StringUtils::toInt(contents.at(0));
const int y = StringUtils::toInt(contents.at(1));
_map = new char[x][y];

Basically the contents vector contains two strings, which I then convert into integers. I then try to initialize the map array but I receive this error:

Error   1   error C2540: non-constant expression as array bound 

And this:

Error   2   error C2440: '=' : cannot convert from 'char (*)[1]' to 'char **'   

And finally this:

    3   IntelliSense: expression must have a constant value 

The last error references the variable y

Can anyone explain what is happening and how I can fix it?

Answer 1

The initialization of 2d array is as following;

char **_map;

_map = new char*[rowsize];

for(int row = 0; row < rowsize; ++row)
{
    _map[row] = new char[columnsize]
}