title: Finding the length of longest repeating?
body: <p>I have tried plenty of different methods to achieve this, and I don't know what I'm doing wrong. </p>
  
  <pre><code>reps=[]
  len_charac=0
  def longest_charac(strng)
      for i in range(len(strng)):
          if strng[i] == strng[i+1]:
              if strng[i] in reps:
                  reps.append(strng[i])
                  len_charac=len(reps)
      return len_charac
  </code></pre>