pass a multi-dimensional array by argument

hello
what's the correct syntax to pass a multidimensional array as argument to a function?
I've tried many times but I always get some error.

a brief example:

Code:

---

void manage_table (int ???) {
        table[x][y] = z;
}

int main () {

        int table[10][10];
        manage_table (table);
}

---

Pass it the same way you declare it.

Code:

---

void manage_table (int table[10][10]) {
        table[x][y] = z;
}

int main () {
        int table[10][10];
        manage_table (table);
}

---

Code:

---

void manage_table (int table[][10]);

---

You always need to specify ALL dimensions except the first one in C.

--
Mats

hmm my example doesn't tell exactly what I really need.
I need to declare array's dimensions at runtime, may that be a trouble?

Hope this example will explain better:

Code:

---

void manage_table (???, int x, int y) {
       
        table[x][y] = <expression>;
}

int main () {

        int width = 12;
        int height = 8;

        int table[width][height];
        manage_table (table, x, y);
}

---

So what did you not understand in the explanation given - the fact that you have two more arguments doesn't influence how you specify your array.

--
Mats

Quote:

---

I need to declare array's dimensions at runtime, may that be a trouble?

---

It doesn't work like that. You can't set the size of an array at runtime unless you manage the array manually with pointers or use a vector object instead of an array.

yes, the two more arguments don't matter, I've added them to make the code more clear.

Quote:

---

Originally Posted by matsp

You always need to specify ALL dimensions except the first one in C.

---

The real difference is that I cannot specify the second dimension, since it is defined at runtime.
I know that one fast solution would be using a mono-dimensional array,

Code:

---

int table[width * height]

---

...but so would be more complicated to program.
Is there another possible solution?

Seeing as it's C++, why not use a vector of vector and simply let the array grow as it needs to?

Otherwise, implement your own 2D array class, and hide all the complexity inside it. If it's always a square you could also enforce that in the class.

--
Mats

Quote:

---

Originally Posted by Banana Man

It doesn't work like that. You can't set the size of an array at runtime unless you manage the array manually with pointers or use a vector object instead of an array.

---

Ok, probably using vectors will be the best solution for me.
Thank you both :)

Quote:

---

Originally Posted by matsp

Seeing as it's C++, why not use a vector of vector and simply let the array grow as it needs to?

---

I've made a mistake in my examples: the array declaration inside the main function.
My program creates that temporary array inside a function, so it doesn't need to be resized: I don't need it anymore after the function returns.
The trouble is that I need to pass the array to another recursive function.
Finally I'll choose for a vector of vectors, you are right.

Why not simply use dynamic memory allocation ?

Code:

---

int a, b;
std::cin >> a;
std::cin >> b;

int** myptr = new int*[a];
for(int i = 0; i < a; i++)
  myptr[i] = new int[b];

---

Quote:

---

Why not simply use dynamic memory allocation ?

---

Due to the good old question: How do I deal with memory leaks?

>> Why not simply use dynamic memory allocation ?
I have yet to hear a single reason why simple dynamic memory allocation should be used instead of a vector in C++.