lines = []
while line = gets
    lines << line.chomp.split(' ').map(&:to_i)
end

N =lines[0][0]
x = []
y = []
for i in 1..N do
  x.push(lines[i][0])
  y.push(lines[i][1])
end

def straight?(i,j,k, x, y)
  if y[i-1] == y[j-1] then
    if y[j-i] == y[k-1] then
      return true
    else
      return false
    end
  else
    if y[j-1] == y[k-1] then
      return false
    else
      ij_slope = (x[j-1] - x[i-1]) / (y[j-1] - y[i-1])
      jk_slope = (x[k-1] - x[j-1]) / (y[k-1] - y[j-1])
      if ij_slope == jk_slope then
        return true
      else
        return false
      end
    end
  end
end
      
def max(x,y)
  if x < y then
    return y
  else
    return x
  end
end

max_radius = 0
for i in 1..(N-2) do
  for j in (i+1)..(N-1) do
    for k in (j+1)..N do
      ij = ((x[j-1] - x[i-1]) ** 2 + (y[j-1] - y[i-1]) ** 2) ** 0.5
      jk = ((x[k-1] - x[j-1]) ** 2 + (y[k-1] - y[j-1]) ** 2) ** 0.5
      ki = ((x[i-1] - x[k-1]) ** 2 + (y[i-1] - y[k-1]) ** 2) ** 0.5
      cos_angle_i = (ij ** 2 + ki ** 2 - jk ** 2) / (2 * ij * ki)
      sin_angle_i = (1 - cos_angle_i ** 2) ** 0.5
      if straight?(i, j, k, x, y) then
        radius = max(ij, max(jk, ki)) / 2
      else
        radius = jk / (2 * sin_angle_i)
      end
      if radius > max_radius then
        max_radius = radius
      end
    end
  end
end

puts max_radius