Двумерные массивы. Сформировать по условию.

#include <iostream>
#include <cstdlib>
#include <ctime>
#include <iomanip>
 
void set_rand_value (int**);
void dump_matrix(int**, unsigned int, unsigned int);
int getsum(int**, unsigned int, unsigned int);
void set_tech_value(int**);
 
const unsigned int HIGH_SIZE = 9;
const unsigned int LOW_SIZE = 3;
const int HIGH_VALUE = 20;
 
int main()
{
 
    int **matrix;
    int *tmp;
    srand(time(0));
 
    matrix = new int* [HIGH_SIZE];
    tmp = new int [HIGH_SIZE * HIGH_SIZE];
 
    for (unsigned int i = 0; i < HIGH_SIZE; ++i)
        matrix[i] = tmp + (HIGH_SIZE * i);
 
    set_rand_value(matrix);
    dump_matrix(matrix, HIGH_SIZE, HIGH_SIZE);
    set_tech_value(matrix);
    dump_matrix(matrix, HIGH_SIZE, HIGH_SIZE);
 
    delete [] matrix;
    delete [] tmp;
 
    return 0;
}
 
void set_rand_value (int **matrix)
{
    for (unsigned int i = 0; i < HIGH_SIZE; ++i)
        for (unsigned int j = 0; j < HIGH_SIZE; ++j)
            matrix[i][j] = rand() % HIGH_VALUE - HIGH_VALUE / 2;
}
 
void dump_matrix(int **matrix, unsigned int row, unsigned int column)
{
    for (unsigned int i = 0; i < row; ++i) {
        for (unsigned int j = 0; j < row; ++j)
            std::cout << std::setw(3) << matrix[i][j];
        std::cout << '\n';
    }
    std::cout << '\n';
}
 
int getsum(int **m, unsigned int row, unsigned int column)
{
    int sum = 0;
 
    for (unsigned int i = row; i < row + LOW_SIZE; ++i)
        for (unsigned int j = column; j < column + LOW_SIZE; ++j)
            if ( !(i == (row + 1) && j == (column + 1) ) )
                sum += m[i][j];
    return sum;
}
 
void set_tech_value(int **matrix)
{
    for (unsigned int i = 0; i < HIGH_SIZE; i += LOW_SIZE)
        for (unsigned int j = 0; j < HIGH_SIZE; j += LOW_SIZE)
            matrix[ i + 1 ][ j + 1 ] = getsum(matrix, i, j);
}