# CS150 list example

# A set of functions for reading in scores and calculating
# various statistics from the input scores.

def get_scores():
    """
    Read user input of numerical scores as floats into a list
    
    Returns:    
        list of scores
    """
    print("Enter the scores one at a time.  Blank score finishes.")
    
    scores = []
    line = input("Enter score: ")
    
    while line != '':
        scores.append(float(line))
        line = input("Enter score: ")
    
    return scores
        
def manual_average(scores):
    """
    Calculate the average of the values in list scores
    
    Args:
        scores: List of numeric scores
    
    Returns:
        Average score as a float
    """
    
    # Compute "manually" without using built-in functions
    sum = 0
    count = 0
    
    for score in scores:
        sum += score
        count += 1
    
    return sum / count

def assign_grades(scores):
    """
    Calculate a letter grade for each numeric score in list.
    If the score is greater than or equal to the average then it receives
    and A.  If it is less, an F.  

    Args:
        scores: List of numeric scores
        
    Returns:
        List of letter grades assigned for each numeric score in corresponding
        order
    """
    avg = manual_average(scores)
    grades = []
    
    for score in scores:
        if score >= avg:
            grades.append("A")
        else:
            grades.append("F")
    
    return grades

def print_class_stats(scores):
    """
    Print out various stats about the list of scores

    Args:
        scores: List of numeric scores
    """
    print("Class max: " + str(max(scores)))
    print("Class min: " + str(min(scores)))
    print("Class average: " + str(manual_average(scores)))
    print("Class grades:")
    
    grades = assign_grades(scores)
    
    for i in range(len(grades)):
        print(str(scores[i]) + " -> " + grades[i])

    
# Get the scores from the user and then print out the stats
scores = get_scores()
print("-" * 10)
print_class_stats(scores)