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# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Linq;

public class Test
{
	public static void Main()
	{
		int n = int.Parse(Console.ReadLine());
		var r = Console.ReadLine().Split().ToArray();
		string s = r[0];
		string t = r[1];
		
		string[] u = new string[2*n];
		for(int i=0;i!=n;i++){
			u[2*i] = s.Substring(i,1);
			u[2*i+1] = t.Substring(i,1);
		}
		
		Console.WriteLine(string.Join("",u));
		
	}
}