#include <stdio.h>
#include <stdlib.h>
 
void set(int** arr, int* data, int rows, int cols) {
    for (int i = 0; i < rows * cols; ++i) {
        arr[((i + 1) / rows) % rows][(i + 1) % cols] = data[i];
    }
}
 
int main() {
    int rows = 3, cols = 3, sum = 0;
    int data[] = {5, 2, 7, 4, 1, 8, 3, 6, 9}; 
    int** arr;
    arr = (int**) malloc(sizeof(int*) * rows);
    for (int i = 0; i < cols; i++) {
        arr[i] = (int*) malloc(sizeof(int) * cols);
    }
 
    set(arr, data, rows, cols);
 
    for (int i = 0; i < rows * cols; i++) {
        sum += arr[i / rows][i % cols] * (i % 2 == 0 ? 1 : -1);
    }
 
    for(int i=0; i<rows; i++) {
        free(arr[i]);
    }
    free(arr);
 
    printf("%d", sum);
}