def get_int
  gets.chop.to_i
end

def get_ints
  gets.chop.split.map(&:to_i)
end

def get_double
  gets.chop.to_f
end

def get_str
  gets.chop
end

def get_strs
  gets.chop.split
end

def main
  n = get_int
  s = get_str
  t = get_str
  chars = []
  0.upto(n-1) do |i|
    chars << s[i]
    chars << t[i]
  end
  puts chars.join("")
end

if __FILE__ == $0
  main
end