def get_words():
    with open("../txt/e042.txt", "r") as f:
        s = f.read()
    words = [w.strip('"') for w in s.split(",")]
    return words


def calculate_word_value(word):
    word = word.upper()
    return sum([ord(letter) - 64 for letter in word])


def get_triangle_numbers(n):
    return {n * (n + 1) // 2 for n in range(1, 101)}


def euler_042():
    triangle_numbers = get_triangle_numbers(100)
    return len([word for word in get_words()
                if calculate_word_value(word) in triangle_numbers])


if __name__ == "__main__":
    assert(calculate_word_value("sky") == 55)
    print("e042.py: " + str(euler_042()))
    assert(euler_042() == 162)