def count_beans(filename):
    '''Return a list giving the number of beans of each color
    recorded in filename.
    Each entry in the list is a two-element list of
    the bean color and the number of occurrences of that color.'''
    color_counts = []
    data_file = open(filename)
    
    for line in data_file:
        color = line.strip() # throw away the ending newline (\n)
        
        color_found = False # whether I've located the right color
        
        # look through color_counts for color
        for entry in color_counts:
            # check if the color of entry is the right one
            if entry[0] == color:
                # this is the color we want
                entry[1] += 1
                color_found = True
                
        if not color_found:
            # didn't find the right color
            # first color of this bean -> add a new entry to list
            color_counts.append([color, 1])
            
    data_file.close()
    return color_counts

def count_beans_dict(filename):
    '''Return a dictionary mapping colors to the number of occurrences
    of that color in filename.'''
    
    color_counts = {}
    
    data_file = open(filename)
    
    for line in data_file:
        color = line.strip() # throw away the ending newline (\n)
        
        # equivalent to the longer section of code below
        color_counts[color] = color_counts.get(color, 0) + 1
        
   #     if color in color_counts: # we've seen the color before
   #         color_counts[color] += 1
   #     else: # haven't seen the color before
   #         color_counts[color] = 1
         
    data_file.close()
    return color_counts


def count_values(dictionary):
    '''return the number of unique values in dictionary'''
    return len(set(dictionary.values()))

    # longer version of the same thing below
        
   # values_set = set() # create an empty set
   # for key in dictionary:
   #     values_set.add(dictionary[key])
   # return len(values_set)