output_description: Print the maximum number of candies that can be collected.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N
      A_{1, 1} A_{1, 2} ... A_{1, N}
      A_{2, 1} A_{2, 2} ... A_{2, N}
attempt: N = int(input())
  a = list(int(i) for i input().split())
  b = list(int(i) for i input().split())
  
  ans = 0
  for n in range(N):
      ap = a[:n]
      bp = b[n-1:]
      apsum = sum(ap)
      bpsum = sum(bp)
      s = apsum +bpsum
      if s > ans:
          ans = s
  print(ans)
problem_description: Statement
  
  We have a 2 \times N grid. We will denote the square at the i-th row and j-th
  column (1 \leq i \leq 2, 1 \leq j \leq N) as (i, j).
  
  You are initially in the top-left square, (1, 1). You will travel to the
  bottom-right square, (2, N), by repeatedly moving right or down.
  
  The square (i, j) contains A_{i, j} candies. You will collect all the candies
  you visit during the travel. The top-left and bottom-right squares also
  contain candies, and you will also collect them.
  
  At most how many candies can you collect when you choose the best way to
  travel?
samples: [{"input": "5\n    3 2 2 4 1\n    1 2 2 2 1", "output": "14\n    \n\nThe number of collected candies will be maximized when you:\n\n  * move right three times, then move down once, then move right once.\n\n* * *"}, {"input": "4\n    1 1 1 1\n    1 1 1 1", "output": "5\n    \n\nYou will always collect the same number of candies, regardless of how you\ntravel.\n\n* * *"}, {"input": "7\n    3 3 4 5 4 5 3\n    5 3 4 4 2 3 2", "output": "29\n    \n\n* * *"}, {"input": "1\n    2\n    3", "output": "5"}]