2.14(Knight Moves)

http://noi.openjudge.cn/ch0205/917/ describe

Background
Mr Somurolov, fabulous chess-gamer indeed, asserts that no one else but him can move knights from one position to another so fast. Can you beat him?
The Problem
Your task is to write a program to calculate the minimum number of moves needed for a knight to reach one point from another, so that you have the chance to be faster than Somurolov.
For people not familiar with chess, the possible knight moves are shown in Figure 1.

Input

The input begins with the number n of scenarios on a single line by itself.
Next follow n scenarios. Each scenario consists of three lines containing integer numbers. The first line specifies the length l of a side of the chess board (4 <= l <= 300). The entire board has size l * l. The second and third line contain pair of integers {0, ..., l-1}*{0, ..., l-1} specifying the starting and ending position of the knight on the board. The integers are separated by a single blank. You can assume that the positions are valid positions on the chess board of that scenario.

Output

For each scenario of the input you have to calculate the minimal amount of knight moves which are necessary to move from the starting point to the ending point. If starting point and ending point are equal,distance is zero. The distance must be written on a single line.

The sample input

3
8
0 0
7 0
100
0 0
30 50
10
1 1
1 1

Sample output

5
28
0

translate :

 

background

The legendary chess player Somurolov Sir asserts , Except for him , No one can move a knight from one position to another so quickly . Can you beat him ?

This problem

Your task is to write a program to calculate the minimum number of movements required for a knight to reach another point from another point , So you have a chance to compare Somurolov faster .

For those who are not familiar with chess , The possible way of Knight walking is shown in the figure 1 Shown .

Input :

Enter the number of scenes in a single line n Start .
Next is n A scenario . Each scene consists of three lines containing integers . The first line specifies the length of the chessboard edge l (4 <= l <= 300). The size of the whole board is l * l, The second and third lines contain a pair of integers {0,…l - 1} *{0,…, l-1} Specify the start and end positions of the knight on the chessboard . Integers are separated by a space . You can assume that these positions are valid positions on the chessboard .

Output :

For each scene entered , You must calculate the minimum amount of movement required for the knight to move from the starting point to the end point . If the start and end points are equal , The distance is zero . The distance must be written on one line .

The sample input

3
8
0 0
7 0
100
0 0
30 50
10
1 1
1 1

Sample output

5
28
0