Moving an array to another function?

[johnt447]

Here is my code

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

//-------------------------------------------------
int input()
{
  int rows;
cout << "please enter the amount of rows " << endl;
cin >> rows;
 rows=rows-1;
 return rows;
}
//--------------------------------------------------




int calc (int rows)
{
  int  matrix [rows][rows];
 int s=0;
  
/////////////////////////////////////////////////////
for ( int r=0; r <= rows && s <= rows ; r++)
    {
   
      cout << " Please enter the value of " << r+1 <<"," << s+1 << endl;
      cin >>  matrix [r][s];
       

      if (r==rows)
	{
	  r=-1;
        s=s+1;
       
      }
    }
////////////////////////////////////////////////////
 return &matrix[0][0];
}
//--------------------------------------------------

int inversion()
{
  return 0;
}
//--------------------------------------------------


int main()
{
  int s=input(); // size of the matrix
  cout << calc(s) << endl;
  return 0;
}

What I'm trying to do is move the array named matrix to main() and then move it to inversion() although i have no idea how to do it.

Any help would be much appreciated.

[Computergeek01]

There are a few ways to do this. By far the easiest (read as sloppiest) is to make the matrix array a global variable, do this by declaring it outside of any function. The classier, and by popular opinion better way, is to pass a pointer to the matrix array to the function. For the later option I would declare the matrix in main() and pass it's pointer as needed to the other functions but that's just me.

[johnt447]

I was wanting to move a pointer from int calc to in main but i have no idea how to do that. :( Could anyone show me please?

[Computergeek01]

That's why I suggested moving the matrix array to the main function, this way you are passing a pointer to the calc() function so you can still work with the array but you don't have to worry about recursivley moving each piece of data back to main().

[Silvermaul]

When you are dealing with large blocks of memory you should use poitners to avoid moving overhead and of course save resources.

[johnt447]

Made some progress

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


//-------------------------------------------------
int input()
{
  int rows;
cout << "please enter the amount of rows " << endl;
cin >> rows;
 rows=rows-1;
 return rows;
}
//--------------------------------------------------




int calc (int rows, int * d)
{
  int s=0;
  for ( int r=0;r <= rows && s <= rows; r++)
    {
   
      cout << " Please enter the value of " << r+1 <<"," << s+1 << endl;
      cin >>  d[r,s];
      cout << d[r,s] << endl;

      if (r==rows)
	{
	  r=-1;
        s=s+1;
       
      }
         

    }
  

  return 0;
}
//--------------------------------------------------

int inversion()
{
  return 0;
}
//--------------------------------------------------


int main()
{
  int s=input();
  int  matrix [s][s];
  //matrix [0][1]=2;
  //cout << &(matrix) << endl;
  calc(s, *(matrix));
  cout << matrix [0][0] << endl;
  return 0;
}

I managed to get it mostly working but for some reason when I do matrix[0][0] it doesn't output 0,0 but seems to output 2,0 which to me makes no sense. Anyone able to shine some light on this?

am guessing its something to do with d[r][s] part.