def part_two(array):
    """Returns the number of entries wherein the defined character appears
    at exactly one of the the specified indices in the string
    """
    valid = 0
    for line in array:
        first = line[3][line[0] - 1] == line[2]
        second = line[3][line[1] - 1] == line[2]
        valid += first != second
    return valid