[<AutoOpen>]
module Program

open System

let read f = stdin.ReadLine() |> f
let reads f = stdin.ReadLine().Split() |> Array.map f

[<EntryPoint>]
let main argv =
    let d = read int
    match d with
    | 22 -> "Christmas Eve Eve Eve"
    | 23 -> "Christmas Eve Eve"
    | 24 -> "Christmas Eve"
    | 25 -> "Christmas"
    |> printfn "%s"
    0