const int width = 100;
const int height = 100;

int **array = (int**)malloc(sizeof(int*)*height);
int *data = (int*)malloc(sizeof(int)*width*height);

for (int x = 0; x < height; ++x) {
    array[x] = &data[x*width];
}

array is now accessible through array[0 through 99][0 through 99]