fun main(args: Array<String>) {
    val input1 = readLine()!!
    val len = input1.toInt()
    val input2 = readLine()!!.split(" ")
    val s = input2[0]
    val t = input2[1]

    println(s.zip(t)
        .map { "${it.first}${it.second}" }
        .joinToString(""))
}