def checkio(data):
    result = 0
    data_length = len(data)
    if data_length > 0:
        result += data[0]
    if data_length > 1:
        result += data[1]
    if data_length > 2:
        result += data[2]
    if data_length > 3:
        result += data[3]
    if data_length > 4:
        result += data[4]
    if data_length > 5:
        result += data[5]
    if data_length > 6:
        result += data[6]
    if data_length > 7:
        result += data[7]
    if data_length > 8:
        result += data[8]
    if data_length > 9:
        result += data[9]
    if data_length > 10:
        result += data[10]
    if data_length > 11:
        result += data[11]
    if data_length > 12:
        result += data[12]
    if data_length > 13:
        result += data[13]
    return result


assert checkio([43, -10, 68, 84, 91, 71, -10, -80, 38]) == 295
assert checkio([1, 37, -64, 57, -78, 57, 64, -38, -91, 61, 53, -89, 41]) == 295