April is taking a road trip with her friends! April's world can be represented by a coordinate plane, where she starts at . There are attractions with coordinate positions she would like to visit. She must visit these coordinates in order, and can travel in a straight line between attractions.

Given a list of attractions to visit in order, can you calculate the total distance traveled?

#### Input Specification

The first line of input will contain one integer, , the number of attractions to visit.

The next lines will each contain two integers and , the coordinates of the attraction.

#### Output Specification

Output the total distance traveled.

Do not round your output. Outputs with a precision error of will be accepted.

#### Subtasks

##### Subtask 1 [15%]

##### Subtask 2 [25%]

##### Subtask 3 [60%]

No further constraints.

#### Sample Input 1

```
3
0 1
2 2
3 3
```

#### Sample Output 1

`4.6502815399`

#### Sample Explanation

This is a diagram of April's trip. Notice how she travels in a straight line between the attractions in the order that they are given.

Remember that the distance between two points on a Cartesian plane is calculated using the Pythagorean Theorem.

#### Sample Input 2

```
5
-2 3
4 -5
5 1
0 1
6 -2
```

#### Sample Output 2

`31.39651773`

## Comments