output_description: If store A is closer, print `A`; if store B is closer, print `B`.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      x a b
attempt: n = int(input())
  a = list(map(int, input().split(" ")))
  x = 0
  y = 0
  a.sort()
  a.reverse()
  for i in range(len(a) - 1):
      if a[i] == a[i + 1]:
          x = a[i]
          p = i + 1
          break
  if x != 0:
      for i in range((p + 1), len(a) - 1):
          if a[i] == a[i + 1]:
              y = a[i]
              break
  print(x * y)
  
problem_description: Statement
  
  Snuke lives at position x on a number line. On this line, there are two stores
  A and B, respectively at position a and b, that offer food for delivery.
  
  Snuke decided to get food delivery from the closer of stores A and B. Find out
  which store is closer to Snuke's residence.
  
  Here, the distance between two points s and t on a number line is represented
  by |s-t|.
samples: [{"input": "5 2 7", "output": "B\n    \n\nThe distances between Snuke's residence and stores A and B are 3 and 2,\nrespectively. Since store B is closer, print `B`.\n\n* * *"}, {"input": "1 999 1000", "output": "A"}]