Given a strictly convex polygon with

vertices

,

,

,

in counterclockwise. Denote

as the polygon with

vertices

,

,

,

. For each

,

,

,

, find the lines which

is symmetric about.
输入描述:
There are multiple test cases. The first line of input contains an integer
(
), the number of test cases. For each test case:
The first line contains an integer
(
), the number of vertices.
The
-th of the following
lines contains two integers
,
(
,
) - the coordinates of
.
It is guaranteed that the vertices are given counterclockwise, and the polygon is strictly convex, i.e., no three vertices are colinear.
It is guaranteed that the sum of
in all test cases does not exceed
.
输出描述:
For each test case:
For each
,
,
,
, output an integer
-- the number of lines which
is symmetric about in the first line, and
lines follow.
In each of the following
lines, output three integers
,
,
(
,
,
), denoting that
is symmetric about the line
.
If there are multiple answers, you can output any of them. For each
, you can output the lines in any order.
示例1
输入
复制
3
4
0 0
1 0
1 1
0 1
3
0 0
3 0
1 1
4
-1000000000 -1000000000
1000000000 -1000000000
1000000000 1000000000
-1000000000 1000000000
输出
复制
1
1 1 -1
4
1 -1 0
0 2 -1
2 0 -1
1 1 -1
0
1
1 1 0
4
1 -1 0
0 1 0
1 0 0
1 1 0