C/C++ for Python programmer [closed]

Answer 1

Alright, lets just start with C for now.

void readH5Data(FILE *file, int ***sample);   // this is for you to implement
void writeH5Data(FILE *file, int ***sample);  // this is for you to implement

int main(int argc, const char *argv[])
{
#define width 3
#define height 3
#define depth 3

    time_t t = time(NULL);

    int ***sample = calloc(width, sizeof(*sample));

    for (int i = 0; i < width; i++)
    {
        sample[i] = calloc(height, sizeof(**sample));
        for (int j = 0; j < height; j++)
        {
            sample[i][j] = calloc(depth, sizeof(***sample));
        }
    }

    for (int i = 0; i < 1000; i++)
    {
        char *filename[64];
        sprintf(filename, "mill2sort-%i-extracted.h5", i);

        // open the file
        FILE *filePtr = fopen(filename, "r");

        if (filePtr == NULL || ferror(filePtr))
        {
            fprintf(stderr, "%s\n", strerror(errno));
            exit(EXIT_FAILURE);
        }
        readH5Data(filePtr, sample);

        fclose(filePtr);
    }

    char filename[] = "mill2sort-extracted-all";

    FILE *writeFile = fopen(filename, "w");

    if (writeFile == NULL || ferror(writeFile))
    {
        fprintf(stderr, "%s\n", strerror(errno));
        exit(EXIT_FAILURE);
    }

    writeH5Data(writeFile, sample);

    fflush(writeFile);
    fclose(writeFile);

    printf("Done in %lli seconds\n", (long long int) (time(NULL) - t));

    for (int i = 0; i < width; i++)
    {
        for (int j = 0; j < width; j++)
        {
             free(sample[i][j]);
        }

        free(sample[i]);
    }

    free(sample);
}

As long as you remember that your array is 3x3x3, you should have no problems overstepping the bounds in your 'writeH5Data' method.