On the plane you are given a set A of n points. The distance from a line p to the set A is the largest of the distances from the points of A to the line p.
Among all lines that pass through a fixed point P, choose the one whose distance to A is as small as possible, and report that smallest distance.
Write a program that:
The first line contains one integer n (1≤n≤100000).
The second line contains two integers: the coordinates of the point P.
Each of the next n lines contains two integers: the coordinates of one point of the set A.
All coordinates are integers whose absolute value does not exceed 106.
Print exactly one real number: the required distance, written with exactly three digits after the decimal point and rounded down (truncated).
The tests are chosen so that any answer within 10−6 of the exact value gives the correct result after this rounding, so computing the distance to about six decimal places of accuracy is enough.