output_description: Print the string formed.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N
      S T
attempt: n = int(input())
  for _ in range(n):
      s, t = input().split()
      c = ""
      i = 0
      j = 0
      f = 0
      for _ in range(len(s) + len(t)):
          if f == 0:
              c += s[i]
              i += 1
              f = 1
          else:
              c += t[j]
              j += 1
              f = 0
      print(c)
  
problem_description: 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.
samples: [{"input": "2\n    ip cc", "output": "icpc\n    \n\n* * *"}, {"input": "8\n    hmhmnknk uuuuuuuu", "output": "humuhumunukunuku\n    \n\n* * *"}, {"input": "5\n    aaaaa aaaaa", "output": "aaaaaaaaaa"}]