title: Indexing list to find duplicate characters in string (Python)
body: <p>So my program is asking the user to input a list of strings and then sort out the strings where if the first letter is repeated again in the same string, it stores it into another list. Here is what I have so far.</p>
  
  <pre><code>iput = []
  i = 0
  final = []
  
  while i &lt; 1:
      iput += [input('Enter words here: ')]
      if not iput[-1]:
          i += 1
  
  i = 0
  z = 1
  while i &lt; len(iput) - 1:
      print(i)
      while iput[i][0] != iput[i][z]:
          if z == len(iput[i]):
              break
          z += 1
  
      i += 1
  
  print(final)
  print(iput)
  </code></pre>
  
  <p>I keep getting a "string index out of range" error and can't think of a way to add the strings that have the requirements stated above. Any suggestions?</p>