##### National Olympiad in Informatics, China, 2010

City YT is a well-designed city. The main roads that run east-west and north-south divide the city into regions. Simply put, we can view city YT as a square with each region also being a square. From this, we know that city YT contains intersections and bidirectional streets (simply referred to as streets). Each street connects a pair of intersections on a main road. The diagram below depicts a map of city YT divided into regions, including intersections and streets.

Little Z is the mayor of this city. Using statistical information, he
has obtained the bidirectional flow rate of people in each street during
rush hours. For the duration of each rush hour, he will know the number
of people going in a specific direction on a specific street. Each
intersection also possesses an **altitude**, which is an issue that
citizens of city YT find very stressful. For a person to climb up to an
altitude of will require him to exhaust units of energy. If
going downhill, no energy will be required. When traveling along a
street, if the difference between the destination altitude and the
initial altitude is (note that can be negative), then a person
will consume units of energy when traveling along the
street (here, represents the largest of two numbers and ).

Little Z also measured the altitude of the intersection at the north-west corner of city to be , and the altitude of the intersection at the south-east corner to be (as depicted in the above diagram). However, there is no way to determine the altitudes of other intersections. Little Z would like to know in the most ideal situation (where you can freely assume altitudes for any intersection), what is the minimum total energy consumed by people climbing the slopes during rush hour?

#### Input Specification

The first line of input consists of a single integer , the meaning of
which is described above.

For the following lines, each line contains a nonnegative
integer representing the number of people (i.e. the flow rate) passing
through a particular street in a particular direction during rush
hour.

The input order is: numbers representing the flow rates of
people going from west to east, followed by numbers
representing the flow rates of people going from north to south,
followed by numbers representing the flow rates of people
going from east to west, finally followed by numbers
representing the flow rates of people going from south to north. For
each directional flow rate, the input order will be from north to south
according to initial locations. If the north-south position of the
initial locations are the same, then the input order will be from west
to east (see sample below).

#### Output Specification

Output a single number, the minimum possible total energy consumption of all people traveling during rush hour if the altitudes were ideal. Round the answer (half-up) to the nearest integers.

#### Sample Input

```
1
1
2
3
4
5
6
7
8
```

#### Sample Output

`3`

#### Explanation

The following diagram depicts the scenario in the sample above. It also indicates the altitudes in an ideal situation.

#### Constraints

For of the test cases: .

For of the test cases: .

For of the test cases: .

For of the test cases: , and .

Also, all flow rates will be integers.

#### Hint

Altitudes may not necessarily be integers.

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