"use strict";
// import bigInt from 'big-integer'

const Main = input => {
  input = input.trim().split("\n");
  const n = input[0]
  input = input[1].split(" ")
  const s = input[0]
  const t = input[1]

  let str = ""
  for (let i = 0; i < n; i++) {
    str += s.charAt(i) + t.charAt(i)
  }

  console.log(str);
};

Main(require("fs").readFileSync("/dev/stdin", "utf8"));
