문제

The city of Osijek has recently been plagued by a swarm of mosquitoes. The solution to this problem was proposed long ago by Mr. Pera, a brave inventor from Beskovci, in an episode of the TV-show Grah called "Globalno selo". Among other inspiring inventions, he presented a mosquito trap. It is basically a box with which you cover the mosquito after it falls for the piece of cheese or "kajmak" you placed there, depending on what your mosquitoes prefer. Simple, isn't it?

If you're lucky, the box can cover more than one mosquito. You have several boxes which are square-shaped but they can, placed parallel to the sides of the table, cover all the mosquitoes? The box, of course, can cover the mosquito with its edge.

입력

The first line of input contains the integer N (2 ≤ N ≤ 20), the number of spotted mosquitoes. Each of the following N lines contains the position of mosquitoes as space-separated integer coordinates X and Y (1 ≤ X, Y ≤ 100) in an imaginary coordinate system whose axes are the sides of the table. At least two mosquitoes will be in different positions.

출력

The first and only line of output must contain the smallest square-shaped box (expressed, of course, in unit squares of the aforementioned coordinate system).

예제 입력 1

3
3 4
5 7
4 3

예제 출력 1

16

예제 입력 2

4
1 5
5 1
10 5
5 10

예제 출력 2

81