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오늘 많네.... 처음에 문제를 잘못 이해해서 꽤나 틀린 문제이다.. 영어를 대충 읽은 탓이좀....한끝 차이로...ㅜㅜ https://www.acmicpc.net/problem/18877 18877번: Social Distancing The first line of input contains $N$ and $M$. The next $M$ lines each describe an interval in terms of two integers $a$ and $b$, where $0 \leq a \leq b \leq 10^{18}$. No two intervals overlap or touch at their endpoints. A cow standing on the endpoint of a www.acmic..