Good Bye 2015 |
---|

Finished |

Virtual contest is a way to take part in past contest, as close as possible to participation on time. It is supported only ICPC mode for virtual contests.
If you've seen these problems, a virtual contest is not for you - solve these problems in the archive.
If you just want to solve some problem from a contest, a virtual contest is not for you - solve this problem in the archive.
Never use someone else's code, read the tutorials or communicate with other person during a virtual contest.

geometry

two pointers

*2900

No tag edit access

The problem statement has recently been changed. View the changes.

×
G. New Year and Cake

time limit per test

2 secondsmemory limit per test

256 megabytesinput

standard inputoutput

standard outputLimak is a little polar bear. According to some old traditions, his bear family prepared a New Year cake. And Limak likes cakes.

As you may know, a New Year cake is a strictly convex polygon with *n* vertices.

Parents won't allow Limak to eat more than half of a cake because he would get sick. After some thinking they decided to cut a cake along one of *n*·(*n* - 3) / 2 diagonals. Then Limak will get a non-greater piece.

Limak understands rules but he won't be happy if the second piece happens to be much bigger. Limak's disappointment will be equal to the difference between pieces' areas, multiplied by two. It can be proved that it will be integer for the given constraints.

There are *n*·(*n* - 3) / 2 possible scenarios. Consider them all and find the sum of values of Limak's disappointment, modulo 10^{9} + 7.

Input

The first line of the input contains a single integer *n* (4 ≤ *n* ≤ 500 000) — the number of vertices in the polygon denoting the cake.

Each of the next *n* lines contains two integers *x*_{i} and *y*_{i} (|*x*_{i}|, |*y*_{i}| ≤ 10^{9}) — coordinates of the *i*-th point.

It's guaranteed that all points are distinct, polygon is strictly convex and points are given in the clockwise order.

Output

Print the sum of values of Limak's disappointment over all possible scenarios modulo 10^{9} + 7.

Examples

Input

5

2 4

2 7

5 7

5 4

3 -2

Output

90

Input

4

-1000000000 -5000000

0 1234567

1 1

-5 -100000000

Output

525185196

Input

8

-10 0

-6 6

0 10

6 6

10 0

6 -6

0 -10

-6 -6

Output

5216

Note

In the first sample possible values of Limak's disappointment are 0, 18, 18, 24, 30.

Codeforces (c) Copyright 2010-2024 Mike Mirzayanov

The only programming contests Web 2.0 platform

Server time: Apr/18/2024 11:25:34 (l2).

Desktop version, switch to mobile version.

Supported by

User lists

Name |
---|