2D arrays such as:Cell **scoreTable.After allocating:
scoreTable = new Ceil*[10];
for(int i = 0 ;i<10;i++)
scoreTable[i] = new Ceil[9];
And I want to save the value like this:scoreTable[i][j]= new Ceil(i,j) in heap,and this can not work in c++.Thanks for help.
scoreTable[i][j]= new Ceil(i,j). You are trying to put Cell* into Cell.
You have to create 2d array of pointers:
auto scoreTable = new Ceil**[10];
for(int i = 0 ;i<10;i++)
scoreTable[i] = new Ceil*[9];
But much better is to use vector:
std::vector< std::vector<Ceil*> > table;
table.resize(10);
for (int i = 0; i < 10; ++i)
{
table[i].resize(9, NULL);
}
table[3][4] = new Ceil();
Once you've allocated your array like this, you'll already have a 2D array of Cell, so you don't need to use the new keyword to change the value.
If you give your Cell class a method like SetValue(i,j), then you can use it like this: scoreTable[i][j].SetValue(i,j);
I want to suggest using std::vector instead. It is much easier to keep track of.
You can replace all of the code above with
std::vector< std::vector< Cell> > scoreTable(10, std::vector<Cell>(9));
This will create scoreTable, which is a vector containing 10 elements of vector<Cell>, each containing 9 cells. In other word, the desired 2D table.
You access the elements in the same way. scoreTable[i][j], where i goes fron 0 to 9, and j from 0 to 8.
If you want to expand with a new row, just say:
scoreTable.push_bach(std::vector<Cell>(9));
For a new column:
for(size_t row = 0; row < scoreTable.size(); ++row) {
scoreTable[row].push_back(Cell());
}
No need for new or delete.
std::vector<std::vector<Cell> >instead?