n = gets.chomp.to_i

x = gets.chomp.split.map(&:to_i).uniq

if x.size == 1
  puts 0
  exit
end

ans = 0xffffffff
x.permutation(2) do |p|
  x1, x2 = p
  ans = [ans, (x1-x2).abs].min
end
puts ans