int64_t** marray_read(size_t* rows, size_t** sizes) {
    *rows = read_size();
    *sizes = (size_t*)malloc(sizeof(size_t) * *rows);

    int64_t** marray;
    marray = (int64_t**)malloc(sizeof(int64_t*) * *rows);

    for(size_t i = 0; i < *rows; i++) {
        *sizes[i] = read_size();
        marray[i] = (int64_t*)malloc(sizeof(int64_t) * *sizes[i]);
        for(size_t j = 0; j < *sizes[i]; j++) {
            marray[i][j] = read_int64();
        }
    }

    return marray;
}