type ABC(stream:System.IO.TextReader) =
  member this.Scan1 f = stream.ReadLine() |> f
  member this.Scan2 f = stream.ReadLine().Split() |> Array.map f |> (fun a -> (a.[0], a.[1]))
  member this.Scan3 f = stream.ReadLine().Split() |> Array.map f |> (fun a -> (a.[0], a.[1], a.[2]))
  member this.Scan4 f = stream.ReadLine().Split() |> Array.map f |> (fun a -> (a.[0], a.[1], a.[2], a.[3]))
  member this.ScanVecH f = stream.ReadLine().Split() |> Array.map f
  member this.ScanVecV n f = [| for i in 1..n -> stream.ReadLine() |> f |]
  member this.ScanMatrix n f  = [ for i in 1..n do yield stream.ReadLine().Split() |> Array.map f ]
  member this.ScanCharMatrix n = [| for i in 1..n -> stream.ReadLine().ToCharArray() |]
  member this.Close () = stream.Close()

let util = ABC(stdin)

let N,M = util.Scan2 int
let As = 
  util.ScanMatrix N int
  |> List.map (Array.skip 1)

[ for i in 1..M do
    if List.forall (fun a -> Array.contains i a) As
      then yield 1
]
|> List.length
|> printfn "%d" 
