> For the complete documentation index, see [llms.txt](https://mr-poston-1.gitbook.io/c++/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://mr-poston-1.gitbook.io/c++/2.-going-beyond-the-basics/2.3-structs/2.3.3-using-structs-line-length.md).

# 2.3.3 Using Structs: Line Length

Structs can be used like any other variable, so it is possible to do many things with them and use them in other data structures.

### Using Structs with Vectors

A good example of extending structs is to use them in a vector. Since a struct is like any other variable, you can create a vector by using the struct name as a type. For example, given the point struct:

```
struct point {
    int x, y;
};
```

You can create and access elements like this:

```
vector<point> points;
point p1;
p1.x = 5;
p1.y = 10;
points.push_back(p1);

// Print x, y
cout << points[0].x << ", " << endl;
```

Notice that you still use the `[ ]` operator then the `.` to acess the vector element and member respectively.

### Other Examples

In thi example, you will see other extensions of structs. As you look through this example, take note of the following:

* The `point` struct is used as a variable type in the `line` struct member definition. This is possible as long as the point struct is defined before the line struct
* The `getPoint` function uses the `point` struct as a return type
* The `lineLength` function needs to access a `point` coordinate from a given line. It does this by stacking the dot variables, i.e. `line.point.x`
* This example uses the `pow` function from the `cmath` library to see more functions from the `cmath` library, you can Google ‘c++ cmath’, or follow this [link](https://www.cplusplus.com/reference/cmath/).

### [Try This Example](https://replit.com/@Poston/233-Using-Structs-Line-Length#main.cpp)


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