import std.algorithm;
import std.array;
import std.conv;
import std.math;
import std.range;
import std.stdio;
import std.string;

void main() {
  auto n = readln.strip.to!int;
  auto s = readln.strip.splitter;
  auto a = s.front; s.popFront;
  auto b = s.front;
  foreach (i; 0 .. n) {
    write (a[i], b[i]);
  }
  writeln;
}

