open System
let R T = stdin.ReadLine()|> T
let RS T = stdin.ReadLine().Split()|>Array.map T
let Mod = (1e9|>int64)+7L
[<EntryPoint>]
let main argv =
    let N = R int
    let S,T = RS string|>fun c -> c.[0],c.[1]
    for i in [0..N-1] do
        stdout.Write S.[i]
        stdout.Write T.[i]
    stdout.WriteLine ""
    0
