def num_vowels(s):
    '''Return the number of vowels in string s.
    The letter "y" is not treated as a vowel.'''
			
    count = 0
    for char in s:
        if char in "aAeEiIoOuU":
            count = count + 1
				
    return count			

def remove_spaces(s):
    '''Return s with any spaces removed.'''

    s_no_spaces = ""
    for char in s:
       if char != " ":
           s_no_spaces += char

    return s_no_spaces

def count_matches(s1, s2):
    '''Return the number of chars in s1 that appear in s2.'''

    common_chars = 0
    for char in s1:
        if char in s2:
            common_chars += 1

    return common_chars

if __name__ == '__main__':

    #test them out
    print num_vowels('hello there fellow'), "sb", 6
    print num_vowels('jjjddjsjsjd jjjj'),"sb", 0
    print num_vowels(''),"sb",0
    print num_vowels('a'),"sb",1
    print num_vowels('b'),"sb",0

    #test them out
    print remove_spaces('hello there fellow'),"sb",'hellotherefellow'
    print remove_spaces('jskrjeksuuyj'),"sb",'jskrjeksuuyj'
    print remove_spaces(''),"sb",''
    print remove_spaces(' '),"sb",''
    print remove_spaces(' b'),"sb",'b'    

    print count_matches("abcde","cdefg"), "sb", 3
    print count_matches("abcde","fghij"), "sb", 0
    print count_matches("abcde",''), "sb", 0
    print count_matches('',''), "sb", 0
    print count_matches('','abcde'), "sb", 0            

    #now, let's write some code to reverse a list.  We won't create a function.
    #just to see that this is possible.
    s = 'abc'
    reverse = ""     # An accumulator
    for char in s:
        reverse = char + reverse
    print reverse, "sb", 'cba'