output_description: If S is a concatenation of two copies of some string, print `Yes`; otherwise,
  print `No`.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N
      S
attempt: N, S = open(0).read().split()
  # print(N, S)
  n = int(int(N) / 2)
  print("Yes" if S[:n] == S[n:] else "No")
  
problem_description: Statement
  
  Given are a positive integer N and a string S of length N consisting of
  lowercase English letters.
  
  Determine whether the string is a concatenation of two copies of some string.
  That is, determine whether there is a string T such that S = T + T.
samples: [{"input": "6\n    abcabc", "output": "Yes\n    \n\nLet T =  `abc`, and S = T + T.\n\n* * *"}, {"input": "6\n    abcadc", "output": "No\n    \n\n* * *"}, {"input": "1\n    z", "output": "No"}]