Scanf.scanf "%d" (fun n ->
    let a = Array.init n (fun _ ->
        Scanf.scanf " %d" (fun p ->
            Array.init p (fun _ ->
                Scanf.scanf " %d" (fun a -> a))
        )
    )
    in
    let m = Array.fold_left (fun acc v -> max acc (Array.length v)) 0 a in
    for j = 0 to m - 1 do
        for i = 0 to n - 1 do
            if Array.length a.(i) > j then Printf.printf "%d " a.(i).(j)
        done
    done;
    print_newline ()
)