5255번 - 2circles 스페셜 저지다국어

We will consider a convex polygon with N vertices. We wish to find the maximum radius R such that two circles of radius R can be placed entirely inside the polygon without overlapping.

The first line of input contains the number N. Each of the next N lines contains a pair of integers xi, yi – representing the coordinates of the ith point, separated by space.

You should output a single number R – the desired radius. Output R with a precision of 3 decimals. You will pass a test if the output differs from the true answer by at most 0.001.

• 3 ≤ N ≤ 50000
• -10⁷ ≤ x_i ≤ 10⁷
• -10⁷ ≤ y_i ≤ 10⁷
• The points are given in trigonometric (anti-clockwise) order.

The maximum radius is obtained when the centers of the two circles are placed on one of the square's diagonals. The radius can be calculated exactly and it is:

\(\dfrac{\sqrt{2}}{2 \times (1 + \sqrt{2})} \approx 0.293\)