def futureValue(currentValue,apr,years):
    '''Given the current value of an investment (int or float),
       an APR (annual percentage rate) (a float), and a number
       of years (an int), return the future value of the investment
       after years years (rounded to an int), assuming simple interest. '''
    
    # e.g. apr = .06  value = 1000
    #
    #  after year 1:  1000 + 1000 * .06 = 1060
    #  after year 2:  1060 + 1060 * .06 = 1123.60
    #  after year 3:  1123.60 + 1123.60 * .06 = 1191.016
    #
    #  note: 1000 + 1000 * .06 = 1000 * (1 + .06)
    #  we'll use this simpler form
    newValue = currentValue 
    for i in range(0,years):
        newValue = newValue * (1 + apr)
    return round(newValue)

def grade(myAns,correctAnswer):
    # You can call this from a print-and-test function for any function
    if myAns == correctAnswer:
       print("Correct, the answer is",myAns)
    else:
       print("My answer is",myAns,"but the correct answer is",correctAnswer)

def printTestFutureValue(currentValue,apr,years,correctAnswer):
    myAns = futureValue(currentValue,apr,years)
    print("The future value of a", currentValue, "investment with APR", apr, "after",years,"years is",myAns)
    grade(myAns,correctAnswer)    

def main():
    #We could make the output look better by calling the "format"
    #function (exercise!)
    #
    printTestFutureValue(1000,.06,3,1191)
    print ("")
    printTestFutureValue(1000,.06,0,1000)
    print ("")
    printTestFutureValue(1000,0,3,1000)
    print ("")
    printTestFutureValue(0,.06,3,0)
    cd1val = futureValue(1000,.06,3)
    cd2val = futureValue(1500,.03,3)
    total = cd1val + cd2val
    #Suze Orman example - 45 year old woman with $74K in retirement to buy a $6400 pool?
    #Denied!  If she invests this now at APR 4% and retires at 65,
    #she would have this much
    #more money
    print ("")    
    print(futureValue(6400,.04,20))

main()