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 Ruby (2.3.3) (judge verdict: Accepted)

def a(n, a_st, b_st)
  result = ""
  a_set = a_st.split('')
  b_set = b_st.split('')
  for a in 0..a_set.size-1
    result = result+a_set[a]
    result = result+b_set[a]
  end
  return result
end

n = gets.chop.split.map(&:to_i)
a_st, b_st = gets.chop.split

print a(n, a_st, b_st)