title: Trying to solve a beginner Python looping assignment
body: <p>I have to make a program that asks the user for a String and then counts and prints the number of vowels in the String. The vowels that count are a, e, i, o, u, y, and the uppercase versions of these. For example, the input "ebony and ivory" would print 7. I also can't use any built-in string functions for this problem. </p>
  
  <p>This is what I have so far: </p>
  
  <pre><code>userString = str(input("Please enter a string:"))
  numVowels = 0
  n=0
  a=0
  e=0
  i=0
  o=0
  u=0
  y=0
  
  
  while (ord(userString[n]) != 0 or ord(userString[n+1])!=0):
  
     if (userString[n] == 'a' or userString[n]=='A'):
         a += 1
         numVowels += 1
     elif (userString[n] == 'e' or userString[n]=='E'):
         e += 1
         numVowels += 1
     elif (userString[n] == 'i' or userString[n]=='I'):
         i += 1
         numVowels += 1
     elif (userString[n] == 'o' or userString[n]=='O'):
         o += 1
         numVowels += 1
     elif (userString[n] == 'u' or userString[n]=='U'):
         u += 1
         numVowels += 1 
     elif (userString[n] == 'y' or userString[n]=='Y'):
         y += 1
         numVowels += 1
     n+=1
  
  print("There are", numVowels, "vowels. There are", a, "A's", e, "E's", i,  "I's", o, "O's", u, "U's, and", y, "Y's, including both uppercase and lowercase versions.")       
  </code></pre>
  
  <p>However I keep getting the error: </p>
  
  <pre><code>IndexError: string index out of range
  </code></pre>
  
  <p>I am using Python 3.</p>