题目描述

Farmer John's N cows (1≤N≤1000) want to organize an emergency "moo-cast" system for broadcasting i
mportant messages among themselves.Instead of mooing at each-other over long distances, the cows dec
ide to equip themselves with walkie-talkies, one for each cow. These walkie-talkies each have a limi
ted transmission radius, but cows can relay messages to one-another along a path consisting of sever
al hops, so it is not necessary for every cow to be able to transmit directly to every other cow.The
cows need to decide how much money to spend on their walkie-talkies. If they spend $X, they will ea
ch get a walkie-talkie capable of transmitting up to a distance of X??√X. That is, the squared dist
ance between two cows must be at most X for them to be able to communicate.Please help the cows dete
rmine the minimum integer value of X such that a broadcast from any cow will ultimately be able to r
each every other cow.

输入格式

The first line of input contains N
The next NN lines each contain the xx and yy coordinates of a single cow.
These are both integers in the range 0…25,000

输出格式

Write a single line of output containing the integer X giving the minimum amount the cows must spend
on walkie-talkies.

样例输入

4
1 3
5 4
7 2
6 1

样例输出

17

提示

Gold