output_description: Print the number of ways to select bags so that the total number of biscuits
  inside is congruent to P modulo 2.
  
  * * *
input_description: Input is given from Standard Input in the following format:
  
      
      
      N P
      A_1 A_2 ... A_N
attempt: n,p=map(int,input().split())
  a=list(map(int,input().split()))
  c=0
  for i in range(n):
    if a[i]%2==1:
      c=1
      break
  if c=1:print(2**(n-1))
  else:
    if p=0:print(2**(n))
    else:print(0)
problem_description: Statement
  
  There are N bags of biscuits. The i-th bag contains A_i biscuits.
  
  Takaki will select some of these bags and eat all of the biscuits inside.
  Here, it is also possible to select all or none of the bags.
  
  He would like to select bags so that the total number of biscuits inside is
  congruent to P modulo 2. How many such ways to select bags there are?
samples: [{"input": "2 0\n    1 3", "output": "2\n    \n\nThere are two ways to select bags so that the total number of biscuits inside\nis congruent to 0 modulo 2:\n\n  * Select neither bag. The total number of biscuits is 0.\n  * Select both bags. The total number of biscuits is 4.\n\n* * *"}, {"input": "1 1\n    50", "output": "0\n    \n\n* * *"}, {"input": "3 0\n    1 1 1", "output": "4\n    \n\nTwo bags are distinguished even if they contain the same number of biscuits.\n\n* * *"}, {"input": "45 1\n    17 55 85 55 74 20 90 67 40 70 39 89 91 50 16 24 14 43 24 66 25 9 89 71 41 16 53 13 61 15 85 72 62 67 42 26 36 66 4 87 59 91 4 25 26", "output": "17592186044416"}]