title: how to not give any output in python
body: <p>I am working on school problem where they give the equation for identifying if ISBN number is valid and give us ten inputs(numbers) and a stop input at the end. </p>
  
  <p>This was my code:</p>
  
  <pre><code>a=str(input())
  b=int(input())
  c=int(input())
  d=int(input())
  e=int(input())
  f=int(input())
  g=int(input())
  h=int(input())
  i=int(input())
  j=int(input())
  u=input() #this is where stop is usually at
  if j==int((int(a)+(2*b)+(3*c)+(4*d)+(5*e)+(6*f)+(7*g)+(8*h)+(9*i))%11):
      print("OK")
  elif j!=int((int(a)+(2*b)+(3*c)+(4*d)+(5*e)+(6*f)+(7*g)+(8*h)+(9*i))%11):
      print("WRONG")
  elif a=="stop":
      print("")
  </code></pre>
  
  <p>The last two lines are there because one of the answers was just one line input: "stop". In this case, the code shouldn't give any output but my code doesn't work and since there is only one input, it gives out an EOF on second line of the code. How can I make this work?</p>