## COCI '20 Contest 2 #2 Odašiljači

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Points: 10 (partial)
Time limit: 1.0s
Memory limit: 512M

Problem types

Sadly, this is the last time Sean will play James Bond.

His mission is to network antennas that are scattered across a vast desert, which can be represented as a 2D plane. He will set the transmission radius of each antenna to be the same non-negative real number . The range of an antenna is defined as the set of all points whose distance to the antenna is at most . If ranges of two antennas have a common point, those antennas can directly communicate. Also, if antennas and can communicate, as well as antennas and , then antennas and are also able to communicate, through antenna .

Sean wants to network the antennas, i.e. make it possible for every two antennas to communicate. Since M has limited his spending for this mission, and larger radii require more money, Sean will choose the smallest possible radius . Help him solve this problem!

#### Input

The first line contains an integer , the number of antennas.

Each of the following lines contains integers and , coordinates of the -th antenna.

#### Output

Output the minimal radius.

Your answer will be considered correct if its absolute or relative error doesn't exceed .

#### Scoring

In test cases worth points it holds that .

#### Sample Input 1

2
1 1
2 2

#### Sample Output 1

0.7071068

#### Sample Input 2

7
2 3
3 4
4 5
0 1
3 1
4 2
1 5

#### Sample Output 2

1.4142135

#### Sample Input 3

4
2020 20
20 2020
2020 2020
20 20

#### Sample Output 3

1000.0000000