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 PHP (5.6.30) (judge verdict: Accepted)

<?php
  fscanf(STDIN, "%d", $n);
  $input = trim(fgets(STDIN));
  $input = explode(" ", $input);
  $word1 = str_split($input[0]);
  $word2 = str_split($input[1]);
  for($i=0; $i<=$n-1; $i++){
    $array[] = $word1[$i];
    $array[] = $word2[$i];
  }
  $word = implode('', $array);
  echo $word;
?>