def main():
    level = get_level()
    score = 0

    ... populate problems with string "X + Y =" ...

    for question in problems:
        incorrect = 0
        while incorrect <= 2:
            if input(question[0]) == str(question[1]):
                score += 1
                break
            else:
                print("EEE")
                incorrect += 1
        if incorrect == 3:
            print(question[0] + str(question[1]))

    print("Score:", score)
    return