Exception in Assignment of 2D array

[sanddune008]

Following is the piece of code:

I a have a function:

void q21_transpose(int **array,int rows,int columns)
{
	int temp,i,j;
		
	for(i=0;i<rows;i++)
	{
	
		for(j=0;j<columns;j++)
		{
			temp = array[i][j]; //Exception is thrown here
			
			array[j][i] = array[i][j];
			array[j][i] = temp;  	
		}
	}
}

Code calling the function:

int a[3][3] = {{1,2,3},{4,5,6},{7,8,9}},**q21_result,i,j;
q21_transpose(a,3,3);

What is wrong with the above highlighted assignment statement?
It throws exception at assignment

Thanks in advance...

[quzah]

Arrays and Pointers

The name of an array is like a pointer to its first element's type. So you 'a' is a pointer to an array of 3 integers. That's different than a pointer to a pointer to an integer.


Quzah.

[sanddune008]

So how do I go about this problem.....
Where in
1. I have to return the 2D array and print them.
2. How to accept argument of type 2D array ?

[quzah]

Read the link I posted. You can't return arrays. You can return a pointer to something you've dynamically allocated, but you can't return an array.


Quzah.

[Salem]

If you have int a[3][3] then the prototype and definition of the function can be

void q21_transpose(int array[3][3],int rows,int columns)
void q21_transpose(int array[][3],int rows,int columns)
void q21_transpose(int (*array)[3],int rows,int columns)
The first one is easy, as it's just a copy/paste of the declaration of the array you want to pass into the function.

The columns parameter is redundant, as it can only ever be 3.