title: Python ValueError: Invalid literal for int () with base 10
body: <p>I keep getting this error in line 87: " words[w][0]+=(int(word[0]))
  ValueError: invalid literal for int() with base 10: ''"</p>
  
  <p>I can't seem to figure out what the issue is any help would be appreciated.</p>
  
  <pre><code>#get a word from the user to analyze
  word=str.lower(input("Enter a word to test: "))
  
  #open up all of the movie reviews
  file=open("movie_reviews.txt","r")
  
  alldata=str.lower(file.read())
  
  file.close()
  
  #create accumulators
  total=0
  numreviews=0
  
  #split data into a list
  splitreviews=alldata.split("\n")
  
  
  #iterate over each review
  for review in splitreviews:
  
      #further split the review into individual words
  
      words=review.split(" ")
  
      if word in words:
  
          total+=int(words[0])
  
          numreviews+=1
  #determine average and if positive or negative or not enough info
  if numreviews==0:
      print(word,"appears",numreviews,"times")
      print("There is no average score for reviews containing the word",word)
      print("Cannot determine if this word is positive or negative")
  else:
      print(word,"appears",numreviews,"times")
      print("Total score was:",total)
      print("Average score for this word is:",total/numreviews)
  
      if total/numreviews&gt;=2:
          print("This is a POSITIVE word!")
      else:
          print("This is a NEGATIVE word!")
  
  
  #set up an empty dictionary to hold all words
  words={}
  
  #import time
  import time
  
  t=time.time()
  print("Initializing sentiment database")
  
  #open up all of movie reviews
  file=open("movie_reviews.txt","r")
  
  alldata=str.lower(file.read())
  
  file.close()
  
  splitreviews=alldata.split("\n")
  
  total=0
  for review in splitreviews:
  
      word=review.split(" ")
  
      #examine every word in this review
      #add it to the sentiment dictionary if necessary
      #or update it if it already exists
      for w in word:
  
          if w not in words: 
              #add it to the dictionary!
              words[w]=[int(word[0]),1]
              total+=1
  
          else:
              #update the word using the new review
              words[w][1]+=1
              words[w][0]+=(str(word[0]))
  
  #all done
  
  print("Sentiment database initialization complete")
  print("Total unique words analyzed:",total)
  print("Analysis took",time.time()-t,"seconds to complete")
  
  
  phrase=str.lower(input("Enter a phrase to test: "))
  
  phraseparts=phrase.split(" ")
  
  totalaverage=0
  num=0
  
  #iterate over each element of phrase pulling info from dictionary
  for p in phraseparts:
      if p not in words:
          print("*",p,"does not appear in any movie reviews")  
      else:
          num+=1
          print("*",p,"appears",words[p][1],"times with an average score of",words[p][0]/words[p][1])
          totalaverage+=words[p][0]/words[p][1]
  
  if num==0:
      print("Not enough words to determine sentiment.")
  
  #determine average if words in the phrace appear in the dictionary
  else:
      print("Average score for this phrase is: ",totalaverage/num)
  
  #determine if it's a positive or negative word
      if totalaverage/num&gt;=2:
          print("This is a POSITIVE phrase")
      else:
          print("This is a NEGATIVE phrase")      
  </code></pre>
  
  <p>For reference the file moviereviews.txt looks like this:</p>
  
  <pre><code>1 A series of escapades demonstrating the adage that what is good for the goose is also good for the gander , some of which occasionally amuses but none of which amounts to much of a story .  
  4 This quiet , introspective and entertaining independent is worth seeking .    
  1 Even fans of Ismail Merchant 's work , I suspect , would have a hard time sitting through this one .  
  3 A positively thrilling combination of ethnography and all the intrigue , betrayal , deceit and murder of a Shakespearean tragedy or a juicy soap opera .  
  1 Aggressive self-glorification and a manipulative whitewash .  
  4 A comedy-drama of nearly epic proportions rooted in a sincere performance by the title character undergoing midlife crisis .  
  1 Narratively , Trouble Every Day is a plodding mess .  
  3 The Importance of Being Earnest , so thick with wit it plays like a reading from Bartlett 's Familiar Quotations  
  1 But it does n't leave you with much . 
  1 You could hate it for the same reason .
  </code></pre>