struct example{
    int n;
    int flm[];
}

struct example *ptr = malloc(sizeof(struct example) + 5*sizeof(int));

ptr->flm[0] = 1;

struct example{
    int n;
    int *notflm;
}

struct example test = {4, malloc(sizeof(int) * 5)};

struct example test;
test.n = 4;
notflm = malloc(sizeof(int) * 5);