Question: When I add this line off code, instead of showing the image, my page gets blank. How can I fix this?

```
<img>
   src={"https://media1.s-nbcnews.com/i/newscms/2019_21/2870431/190524-classic-american-cheeseburger-ew-207p_d9270c5c545b30ea094084c7f2342eb4.jpg"}  alt={''}
</img>

```

Answer: 
It's correct that the overload will [default insert](https://en.cppreference.com/w/cpp/named_req/DefaultInsertable) elements.

But you have to keep on reading, as default insertion means that the values inserted will be [value initialized](https://en.cppreference.com/w/cpp/language/value_initialization), and value-initializing an aggregate (like `std::array`) will value-initialize all elements in the aggregate.

And value initialization of `double` values will be the same as [zero-initialization](https://en.cppreference.com/w/cpp/language/zero_initialization).

So all elements in each array of the vector will be initialized to zero.
To be sure that your arrays are zero-initialized, you can add a 1-element initializer list as a second argument to the `a` constructor call:

```cpp
std::vector<std::array<double, 10>> a(10, { 0.0, });

```

This will initialize *each* element (array) using that list, as it will be using constructor version #3 described [here in cppreference](https://en.cppreference.com/w/cpp/container/vector/vector).

The 'value' argument used to initialize each array will use aggregate initialization ([see here](https://en.cppreference.com/w/cpp/container/array)), which will zero-initialize any 'missing' values in the list.