I want to make an array of my struct type, but it is not defined in sequence, e.g, randomly I can do `array[3] = mystruct_t;` `array[5] = mystruct_t`(`3` and `5` is defined at run-time by user input). I had tried:

it's the "ideal", but can't hold null-pointers:

```
static struct mystruct_t foo_inputs[SIZE];

```

So, I tried:

```
static struct mystruct_t *foo_inputs;

```

and then:

```
foo_inputs[x] = NULL;

```

But I get an warning:

```
 error: incompatible types when assigning to type ‘struct mystruct_t’ from type ‘void *’

```

Ideas to implement it?