require 'bigdecimal'

height = []
x = gets
until x.nil?
 y = x.to_f
 height << y
 x = gets
end

maxh = height.max
minh = height.min
maxs = maxh.to_s
mins = minh.to_s 
ansf = (BigDecimal(maxs) - BigDecimal(mins)).to_f
ans = ansf.floor(2)
puts ans
