output_description: Print the number of ways to climb up the stairs under the condition, modulo 1\
  000\ 000\ 007.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N M
      a_1
      a_2
       .
       .
       .
      a_M
attempt: def inputs(num_of_input):
      ins = [input() for i in range(num_of_input)]
      return ins
  
  
  def solve(inputs):
      [N, M] = list(map(lambda x: int(x), inputs[0].split()))
      broke_steps = {}
      for b in map(lambda x: int(x), inputs[1:]):
          broke_steps[b] = True
  
      SSSS = 1000000007
  
      patterns = [1]
      for step in range(1, N + 1):
          if step in broke_steps:
              ap = 0
          elif step == 1:
              ap = 1
          else:
              ap = (patterns[step - 1] + patterns[step - 2]) % SSSS
          patterns.append(ap)
  
      return patterns[-1]
  
  
  if __name__ == "__main__":
      first = input()
      [N, M] = list(map(lambda x: int(x), first.split()))
      inputs_str = inputs(M)
      inputs_str.insert(0, first)
      ret = solve(inputs_str)
      print(ret)
  
problem_description: Statement
  
  There is a staircase with N steps. Takahashi is now standing at the foot of
  the stairs, that is, on the 0-th step. He can climb up one or two steps at a
  time.
  
  However, the treads of the a_1-th, a_2-th, a_3-th, \ldots, a_M-th steps are
  broken, so it is dangerous to set foot on those steps.
  
  How many are there to climb up to the top step, that is, the N-th step,
  without setting foot on the broken steps? Find the count modulo 1\ 000\ 000\
  007.
samples: [{"input": "6 1\n    3", "output": "4\n    \n\nThere are four ways to climb up the stairs, as follows:\n\n  * 0 \\to 1 \\to 2 \\to 4 \\to 5 \\to 6\n  * 0 \\to 1 \\to 2 \\to 4 \\to 6\n  * 0 \\to 2 \\to 4 \\to 5 \\to 6\n  * 0 \\to 2 \\to 4 \\to 6\n\n* * *"}, {"input": "10 2\n    4\n    5", "output": "0\n    \n\nThere may be no way to climb up the stairs without setting foot on the broken\nsteps.\n\n* * *"}, {"input": "100 5\n    1\n    23\n    45\n    67\n    89", "output": "608200469\n    \n\nBe sure to print the count modulo 1\\ 000\\ 000\\ 007."}]