import java.util.Scanner;

fun main (args : Array<String>) {
  val input = Scanner(System.`in`)
  
  while (input.hasNext()) {
    val N = input.nextInt()
    val S = input.next()
    val T = input.next()
    val ST = StringBuilder()
    
    for(i in 0..(S.length - 1)) {
      ST.append(S[i])
      ST.append(T[i])
    }
    
    println(ST)
  }
}