let solve rc_lst =
    let rec solve' lst (result: Set<int * int> list) =
        //eprintfn "%A" result

        match lst with
        | [] -> true
        | x::xs ->
            let r0, c0, r1, c1 = x
            let result = match result with
                         | [] -> [set[(r0, c0)]; set[(r1, c1)]]
                         | _ ->
                            result
                            |> List.map (fun s ->
                                match (Set.contains (r0, c0) s), (Set.contains (r1, c1) s) with
                                | true, true -> []
                                | false, true -> [(Set.add (r0, c0) s)]
                                | true, false -> [(Set.add (r1, c1) s)]
                                | false, false -> [(Set.add (r0, c0) s); (Set.add (r1, c1) s)])
                            |> List.concat
            if result = [] then false
            else solve' xs result

    solve' rc_lst []

let () =
    let n = stdin.ReadLine() |> int

    let rc_lst =
        seq {
            for _ in 1..n do
                let r0, c0, r1, c1 = stdin.ReadLine()
                                     |> fun s -> s.Split()
                                     |> Array.map int
                                     |> fun arr -> arr.[0], arr.[1], arr.[2], arr.[3]
                yield (r0, c0, r1, c1) }
        |> List.ofSeq

    solve rc_lst
    |> function | true -> "YES" | false -> "NO"
    |> printfn "%s"