def item_in_range(item, id_range):
    start = id_range[0]
    end = id_range[1]
    return start <= item <= end

def squash_ranges(id_ranges):

    while True:
        id_ranges_size = len(id_ranges)

        squash_range = []

        squash_range.append(id_ranges[0].copy())
        for checker in id_ranges:

            overlap = False
            for candidate in squash_range:
                # Squash if checker min within candidate range or otherway around
                if item_in_range(checker[0], candidate) or item_in_range(candidate[0], checker):
                    overlap = True
                    candidate[0] = min(checker[0],candidate[0])
                    candidate[1] = max(checker[1],candidate[1])

            if not overlap:
                squash_range.append(checker.copy())

        id_ranges = squash_range.copy()

        if id_ranges_size == len(id_ranges):
            # If no changes, break
            break
    return id_ranges



def read_input(filename):
    id_ranges = []

    for line in open(filename).read().splitlines():

        if line == "":
            return id_ranges

        id_range = line.split("-")
        id_ranges.append([int(id_range[0]),int(id_range[1])])

# filename = "day05/my_example_input"
# filename = "day05/example_input" # 14
filename = "day05/input" # 358155203664116

id_ranges = read_input(filename)

id_ranges = squash_ranges(id_ranges)

counter = 0
for id_range in id_ranges:
    counter += (id_range[1] - id_range[0]) + 1 # ranges are inclusive...


print(f"Fresh items: {counter}")