text: # -*- coding: utf-8 -*-
  """
  Created on Sat Jan  2 10:41:47 2021
  
  @author: RAMYA
  """
  
  # print(" this is a single line")
  
  # print("Hello world")
  
  # a = 2**45
  
  # print(a)
  
  
  
  # you are given two inputs
  
  a= 7 #int(input())
  b= [2,3,1,4,6,5,5]#[int(i) for i in input().split()]
  
  
  count = 0
  for i in range(2,len(b)-1):
      print(i, ":",b[i-2], b[i-1],b[i],b[i+1])
      if b[i-2]+b[i-1]==b[i]+b[i+1]:
          count+=1
  
  print(count)
  
  
  # count =0
  # for i in range(3,len(b)):
  #     print(i, ":",b[i-3], b[i-2],b[i-1],b[i])
  #     if b[i-3]+b[i-2]==b[i-1]+b[i]:
  #         count+=1
  
  # print(count)
  final = ""
  for i in range(len(b)):
      if i%3==0:
          final= final+" "+str(b[i])
  
  print(final)
  
  
  
  final = []
  for i in range(len(b)):
      if i%3==0:
          final.append(str(b[i]))
  
  output = " ".join(final)
  print(output)
  
  
  
  
  
  
  