let ``No.135 とりあえず1次元の問題``() =

  let n = stdin.ReadLine() |> int
  let xn =
     stdin.ReadLine().Split(' ')
    |> Array.map (int)
    |> Array.sort

  seq {
    for i in [2..xn.Length] do
     if xn.[i-1] <> xn.[i-2] then 
      yield (xn.[i-1] - xn.[i-2]) 
  }
  |> fun sq ->
     if   sq |> Seq.length = 0 then 0
     else sq |> Seq.min 
  |> stdout.WriteLine
  
``No.135 とりあえず1次元の問題``()