Problem:
Score : 200 points

Problem Statement

Given are strings s and t of length N each, both consisting of lowercase English letters.

Let us form a new string by alternating the characters of S and the characters of T, as follows: the first character of S, the first character of T, the second character of S, the second character of T, ..., the N-th character of S, the N-th character of T. Print this new string.

Constraints

1 \leq N \leq 100

|S| = |T| = N

S and T are strings consisting of lowercase English letters.

Input

Input is given from Standard Input in the following format:

N
S T

Output

Print the string formed.

Sample Input 1

2
ip cc

Sample Output 1

icpc

Sample Input 2

8
hmhmnknk uuuuuuuu

Sample Output 2

humuhumunukunuku

Sample Input 3

5
aaaaa aaaaa

Sample Output 3

aaaaaaaaaa

Solution in C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <bits/stdc++.h>

using namespace std;

#define FOR(i, N) for (int i = 0; i < (int)N; i++)
#define FORIN(i, a, b) for (int i = a; i < (int)b; i++)
#define ALL(x) (x).begin(), (x).end()
#define MOD 1000000007
#define INF (1 << 29)
#define LLINF (1LL << 60)
#define DEBUG(...) debug(__LINE__, ":" __VA_ARGS__)

using Pi = pair<int, int>;
using ll = long long;

string to_string(string s) { return s; }
template <class S>
string to_string(unordered_set<S> s);
template <class S>
string to_string(set<S> s);
template <class S, class T>
string to_string(map<S, T> m);
template <class T>
string to_string(vector<T> v);

template <class S, class T>
string to_string(pair<S, T> p) {
  return "{" + to_string(p.first) + "," + to_string(p.second) + "}";
}

template <class S>
string to_string(unordered_set<S> s) {
  string ret = "{";
  for (S x : s) ret += to_string(x) + ",";
  return ret + "}";
}

template <class S>
string to_string(set<S> s) {
  string ret = "{";
  for (S x : s) ret += to_string(x) + ",";
  return ret + "}";
}

template <class S, class T>
string to_string(map<S, T> m) {
  string ret = "{";
  for (pair<S, T> x : m) ret += to_string(x) + ",";
  return ret + "}";
}

template <class T>
string to_string(vector<T> v) {
  string ret = "{";
  for (int i = 0; i < (int)v.size() - 1; ++i) {
    ret += to_string(v[i]) + ",";
  }
  if (v.size() > 0) {
    ret += to_string(v.back());
  }
  ret += "}";
  return ret;
}

void debug() { cerr << endl; }

template <class Head, class... Tail>
void debug(Head head, Tail... tail) {
  cerr << to_string(head) << " ";
  debug(tail...);
}

void print() { cout << endl; }

template <class Head, class... Tail>
void print(Head head, Tail... tail) {
  cout << to_string(head);
  print(tail...);
}

int main() {
  cin.tie(0);
  ios::sync_with_stdio(0);
  int N;
  string s, t;
  cin >> N >> s >> t;
  FOR(i, N) { cout << s[i] << t[i]; }
  cout << endl;
  return 0;
}