output_description: Print the minimum possible value of (i \times j) \mbox{ mod } 2019 when i and
  j are chosen under the given condition.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      L R
attempt: L, R = map(int, input().split(' '))
  
  N = 2019
  
  
  ans = 2019
  
  for i in range(L, R):
      for j in range(i + 1, R + 1):
          mod = (i * j) % N
          if ans > mod:
              ans = mod
          if ans = 0:
              print(ans)
              exit(0)
  
  print(ans)
problem_description: Statement
  
  You are given two non-negative integers L and R. We will choose two integers i
  and j such that L \leq i < j \leq R. Find the minimum possible value of (i
  \times j) \mbox{ mod } 2019.
samples: [{"input": "2020 2040", "output": "2\n    \n\nWhen (i, j) = (2020, 2021), (i \\times j) \\mbox{ mod } 2019 = 2.\n\n* * *"}, {"input": "4 5", "output": "20\n    \n\nWe have only one choice: (i, j) = (4, 5)."}]