text: str

with open("input.txt") as f:
    text = f.read()

total: int  = 0


ranges_str, dates = text.split("\n\n")

ranges: list[list[int, int]] = []
for range_str in ranges_str.splitlines():
    start, stop = range_str.split("-")
    ranges.append([int(start), int(stop)])

range_wo_overlap: list[list[int, int]] = []

bozo2 = 1
bozo = True
while bozo:
    bozo = False
    range_wo_overlap: list[list[int, int]] = []
    for start, stop in ranges[::bozo2]:
        placed: bool = False
        for i, value in enumerate(range_wo_overlap):
            start2, stop2 = value
            if (start2 <= start <= stop2):
                if (stop > stop2):
                    range_wo_overlap[i][1] = stop
                    bozo = True
                placed = True
                break
            if (start2 <= stop <= stop2):
                if (start < start2):
                    range_wo_overlap[i][0] = start
                    bozo = True
                placed = True
                break
        if not placed:
            range_wo_overlap.append([start, stop]) 
    ranges = range_wo_overlap
    bozo2 *= -1

print(ranges)

for start, stop in ranges:
    total += stop - start + 1

print(total)