On the occasion of the 80th National Day anniversary on September 2, many delegates attended the celebration at the historic Ba Dinh Square. The square can be considered a coordinate system, the i-th delegate is standing at the coordinates ~x_i, y_i~. The organizing committee needs to stand at a convenient location to be able to use the loudspeaker to announce to the N delegates present at the square so that the loudspeaker can announce to the delegates present within the hearing range of R. Determine the smallest R to be able to announce to the N delegates about the content, program and necessary information.

Input: From the standard device in the following format:

• The first line records an integer N (N ≤ 100)
• The next N lines, each line records 2 integers ~x_i, y_i~ representing the coordinates of the i-th delegate.

Output: Write to the standard device a single real number with 3 decimal places as the required result.

Exam:

Input

3
0 0
0 1
1 1

Ouput

0.707