#P7146. Laser
Laser
Problem Description
There are $n$ enemies on a two-dimensional plane, and the position of the i-th enemy is ($x_i$,$y_i$)
You now have a laser weapon, which you can place on any grid $(x,y)$(x, y are real numbers) , and the weapon fires a powerful laser that for any real number k, enemies at coordinates $(x+k, y), (x, y+k), (x+k, y+k), (x+k, y-k)$ will be destroyed.
You are now wondering if it is possible to destroy all enemies with only one laser weapon.
Input
The first line of input is a positive integer $T(T\leq 10^5)$ representing the number of data cases.
For each case, first line input a positive integer $n$ to represent the position of the enemy.
Next $n$ line, the i-th line inputs two integers $x_i, y_i(-10^8 \leq x_i,y_i \leq 10^8)$ represents the position of the i-th enemy.
The data guarantees that the sum of $n$ for each test case does not exceed 500,000
Output
For each cases, If all enemies can be destroyed with one laser weapon, output “YES“, otherwise output “NO“(not include quotation marks).
2
6
1 1
1 3
2 2
3 1
3 3
3 4
7
1 1
1 3
2 2
3 1
3 3
1 4
3 4
YES
NO