n = gets.to_i
array = []
ans = 0
n.times do 
  x, y = gets.split.map(&:to_i)
  longest = 0
  array.each do |xx, yy|
    long = (xx-x).abs+(yy-y).abs
    longest = long if long > longest
  end
  array << [x,y]
  ans = longest if longest > ans
end
p ans