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;
typedef long long ll;
typedef pair<int,int> P;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)

/*新たな文字列の偶数文字目をSの各文字に変える
*/


int main() {
  int N;
  cin >> N;
  string S,T;
  cin >> S >> T;
  string X;
  for(int i = 0;i<2*N;i++){
      X.push_back('a');
  }

  for(int i = 0;i<2*N;i++){
      if(i%2 == 0) X[i] = S[i/2];
      else X[i] = T[i/2];
  }
  cout << X << endl;

 }