What is the proof behind Half Sequence's Solution (Codechef Cook-Off) ?

Правка en2, от aopo, 2021-09-20 11:21:06

The official editorial of the Half Sequence says

Reason they give

But, what is the proof behind it? I mean what is the intution behind saying this? Can someone give a formal proof for it.


  Rev. Язык Кто Когда Δ Комментарий
en2 Английский aopo 2021-09-20 11:21:06 1
en1 Английский aopo 2021-09-20 11:18:19 789 Initial revision (published)