output_description: Print the lexicographically smallest string after performing exactly K
  operations on s.
  
  * * *
input_description: The input is given from Standard Input in the following format:
  
      
      
      s
      K
attempt: a=[ord(i) for i in input()]
  s = int(input())
  for i in range(len(a)):
   if 26+97-a[i]<=s && a[i]!=97:
       aa=a[i]
       a[i]=97
       s-=26+97-aa
  if s>0:
   a[-1]+=s
   if a[-1]>97+25:
       a[-1]=(a[-1]-97)%26+97
  b=""
  for i in a:
   b+=chr(i) 
  print(b)
problem_description: Statement
  
  Mr. Takahashi has a string s consisting of lowercase English letters. He
  repeats the following operation on s exactly K times.
  
    * Choose an arbitrary letter on s and change that letter to the next alphabet. Note that the next letter of `z` is `a`.
  
  For example, if you perform an operation for the second letter on `aaz`, `aaz`
  becomes `abz`. If you then perform an operation for the third letter on `abz`,
  `abz` becomes `aba`.
  
  Mr. Takahashi wants to have the lexicographically smallest string after
  performing exactly K operations on s. Find the such string.
samples: [{"input": "xyz\n    4", "output": "aya\n    \n\nFor example, you can perform the following operations: `xyz`, `yyz`, `zyz`,\n`ayz`, `aya`.\n\n* * *"}, {"input": "a\n    25", "output": "z\n    \n\nYou have to perform exactly K operations.\n\n* * *"}, {"input": "codefestival\n    100", "output": "aaaafeaaivap"}]