#!/usr/bin/env python3
# -*- coding: utf-8 -*-
import  time

#file = "./ex.txt"
file = "./input.txt"

def merge_intervals(intervals):
    if not intervals:
        return []
    intervals = sorted(intervals, key=lambda x: x[0])
    merged = [intervals[0]]
    for start, end in intervals[1:]:
        last_start, last_end = merged[-1]
        if start <= last_end:
            merged[-1] = (last_start, max(last_end, end))
        else:
            merged.append((start, end))
    return merged

if __name__ == "__main__":
    time_start = time.time()
    solution = 0
    fresh_ranges = []
    input_file = open(file, "r")
    for line in input_file:
        line = line.strip()
        if line == "" or "-" not in line:
            continue
        else:
            a,b = line.split('-')
            a = int(a)
            b = int(b)
            fresh_ranges.append([a,b])
    id_set = set()
    merged_ranges = merge_intervals(fresh_ranges)
    for start, end in merged_ranges:
        solution += (end - start + 1)
    print(f"Solution: {solution} benötigte Zeit = {time.time()-time_start} s")