Example of two and three dimensional pointers

Welcome everyone,
I did a little problem to practice with pointers to other pointers. In this case, I did a matrix and pass it by a function than expect the reference of it.

The example compute the multiplication of two matrices.

Note: This post was inspired answering that post: http://www.cplusplus.com/forum/general/86553/


Enjoy it:

#include <iostream>
#include <algorithm>
#include <stdlib.h>

using namespace std;

void fill(int& value){
    static int val = 0;
    val++;

    value = val;
}

void zero(int& value){
    value = 0;
}


void mult(int* **A,int* **B,int* **result, const int SIZE) {
    for (int i = 0; i < SIZE; i++)
        for (int j = 0; j < SIZE; j++)
            for (int k = 0; k < SIZE; k++)
                (*result)[i][j] += B[0][i][k] * (*A)[k][j];
}

int main(){
    int *vector;
    const int SIZE = 3;

    //reserve memory:
    vector = (int*) malloc(sizeof(int) * SIZE);
    for_each(vector,vector + SIZE,fill); //fill

    //print
    for(int i = 0 ; i < SIZE ; i++)
        cout << vector[i] << ", ";
    cout << endl << endl << endl;

    //reserve memory for a pair of matrices:
    int**matrix;
    matrix = (int**) malloc(sizeof(int*) * SIZE );
    for(int i = 0 ; i < SIZE ; i++ )
        matrix[i] = (int*) malloc(sizeof(int) * SIZE);

    int**result;
    result = (int**) malloc(sizeof(int*) * SIZE );
    for(int i = 0 ; i < SIZE ; i++ )
        result[i] = (int*) malloc(sizeof(int) * SIZE);
    //***************************

    //fill matrix:
    for_each(matrix[0],matrix[0] + SIZE,fill);  for_each(result[0],result[0] + SIZE,zero);  
    for_each(matrix[1],matrix[1] + SIZE,fill);  for_each(result[1],result[1] + SIZE,zero);
    for_each(matrix[2],matrix[2] + SIZE,fill);  for_each(result[2],result[2] + SIZE,zero);

    //print it
    for(int i = 0 ; i < SIZE ; i++){
        for(int j = 0 ; j < SIZE ; j++)
            cout << matrix[i][j] << ", ";
        cout << endl;
    }
    cout << endl << endl << endl;

    mult(&matrix, &matrix, &result, SIZE);
    //print it
    for(int i = 0 ; i < SIZE ; i++){
        for(int j = 0 ; j < SIZE ; j++)
            cout << result[i][j] << ", ";
        cout << endl;
    }
    cout << endl << endl << endl;

    system("pause");

    return 0;
}