title: How to calculate and print the least and most occurring vowels in a string?
body: <p>I am required to input a string, calculate the number of vowels in that string, and then calculate the most and least occurring vowels. When the string contains no vowels at all, a message should print saying "no vowels were entered". Where there are vowels which occur the same number of times (e.g. if a and e both occur twice ), these vowels should both appear as being most or least occurring. However, if some vowels are in the string but not all, then the ones which do not appear in the sting should be ignored (rather than printing "a=0"). I think the counting part at the start is correct to an extent, but not quite. As for the most/least occurrences, I don't even know where to begin. Any help would be appreciated!</p>
  
  <pre><code>myString = str(input("Please type a sentence: ").lower())
  
  count = [0, 0, 0, 0, 0]
  
  for vowel in myString:
  
      if vowel == "a" :
          count[0]=count[0]+1
      if vowel == "e" :
          count[1]=count[1]+1
      if vowel == "i" :
          count[2]=count[2]+1
      if vowel == "o" :
          count[3]=count[3]+1
      if vowel == "u" :
          count[4]=count[4]+1
  
      while count[0] &gt; 0:
          print ("acount :",count[0])
          break
      while count[1] &gt; 0:
          print ("ecount :",count[1])
          break
      while count[2] &gt; 0:
          print ("icount :",count[2])
          break
      while count[3] &gt; 0:
          print ("ocount :",count[3])
          break
      while count[4] &gt; 0:
          print ("ucount :",count[4])
          break
  
  else:
      if count[0] == 0 and count[1] == 0 and count[2] == 0 and count[3] == 0 and count[4] == 0:
          print ("No vowels were found")
  </code></pre>