N = int(input())
pre_points = []
pre_gx,pre_gy = 0,0
for _ in range(N):
    x,y = list(map(int,input().split()))
    pre_gx += x
    pre_gy += y
    pre_points.append((x,y))
pre_gx /= N
pre_gy /= N

pre_farest_point_dist = 0
for x,y in pre_points:
    pre_farest_point_dist = max(pre_farest_point_dist,((pre_gx - x) * (pre_gx - x) + (pre_gy - y) * (pre_gy - y))**(1/2))

after_gx,after_gy = 0,0
after_points = []
for _ in range(N):
    z,w = list(map(int,input().split()))
    after_gx += z
    after_gy += w
    after_points.append((z,w))
after_gx /= N
after_gy /= N

after_farest_point_dist = 0
for x,y in pre_points:
    after_farest_point_dist = max(after_farest_point_dist,((after_gx - x) * (after_gx - x) + (after_gy - y) * (after_gy - y))**(1/2))

print((after_farest_point_dist / pre_farest_point_dist)**(1/2))