Thread: two dimensional array

I am trying to write a program that creates a magic square of two dimensions. The size of the array needs to be decided by the user so it can't be predefined. I've come across a few different ways to allocate memory for a 2 dimensional array but none without a predetermined size. Is there a way to get this to work?

Code:

int main(void)
{
int order;
double TwoDimArray[order][order];

cout <<"This program will create a magic square of an odd order\n";
cout <<"Please enter the order number you would like:\n";
cin >> order;

THANK YOU!

I added that after reading 'order' and added header #include <vector> but now it is saying template argument 1 and template argument 2 are invalid errors for that line?

sorry but now I am recieving a conflicting declaration error for that line?

Code:

#include <iostream>
#include <vector>
using namespace std;

void MagicSquare ( double matrix, int n );
void DisplaySquare ( int matrix, int n );

int main(void)
{
int order;
double TwoDimArray[order][order];

cout <<"This program will create a magic square of an odd order\n";
cout <<"Please enter the order number you would like:\n";
cin >> order;
std::vector<std::vector<double> > TwoDimArray(order, std::vector<double>(order));
if (order%2==1)
    MagicSquare( TwoDimArray, order );
    else{
        while (order%2==0){
        cout <<"Please enter an odd number:\n";
        cin >> order;
        }
        MagicSquare( TwoDimArray, order );

    }
}
void MagicSquare ( double matrix, int n )
{
int max = n * n;
int i=0;
int j=n/2;     // start position

  for (int k=1; k<=max; ++k)
  {
    matrix[i][j] = k;

    i--;
    j++;

    if (k%n == 0)
    {
      i += 2;
      --j;
    }
    else
    {
      if (j==n)
        j -= n;
      else if (i<0)
        i += n;
    }
  }
}
void DisplaySquare( &matrix, int n)
{
int i;
int j;
  for (int i=0; i<n; i++)
  {
    for (int j=0; j<n; j++)
      printf(" %3d", matrix[i][j]);

    printf("\n");
  }

  printf("\n\n");
}

do i need to change the type of 'order'?