output_description: Output an integer representing the minimum number of iterations needed for the
  rewrite operation.
  
  * * *
input_description: Inputs are provided from Standard Input in the following form.
  
      
      
      S
attempt: import sys, re
  from collections import deque, defaultdict, Counter
  from math import ceil, sqrt, hypot, factorial, pi, sin, cos, radians
  from itertools import accumulate, permutations, combinations, product, groupby
  from operator import itemgetter, mul
  from copy import deepcopy
  from string import ascii_lowercase, ascii_uppercase, digits
  from bisect import bisect, bisect_left
  from fractions import gcd
  from heapq import heappush, heappop
  from functools import reduce
  
  
  def input():
      return sys.stdin.readline().strip()
  
  
  def INT():
      return int(input())
  
  
  def MAP():
      return map(int, input().split())
  
  
  def LIST():
      return list(map(int, input().split()))
  
  
  def ZIP(n):
      return zip(*(MAP() for _ in range(n)))
  
  
  sys.setrecursionlimit(10**9)
  INF = float("inf")
  mod = 10**9 + 7
  
  S = input()
  T = "CODEFESTIVAL2016"
  print(sum(x != y for x, y in zip(S, T)))
  
problem_description: Statement
  
  CODE FESTIVAL 2016 is going to be held. For the occasion, Mr. Takahashi
  decided to make a signboard.
  
  He intended to write `CODEFESTIVAL2016` on it, but he mistakenly wrote a
  different string S. Fortunately, the string he wrote was the correct length.
  
  So Mr. Takahashi decided to perform an operation that replaces a certain
  character with another in the minimum number of iterations, changing the
  string to `CODEFESTIVAL2016`.
  
  Find the minimum number of iterations for the rewrite operation.
samples: [{"input": "C0DEFESTIVAL2O16", "output": "2\n    \n\nThe second character `0` must be changed to `O` and the 14th character `O`\nchanged to `0`.\n\n* * *"}, {"input": "FESTIVAL2016CODE", "output": "16"}]