PAST5M
https://gyazo.com/d4601d3337d3e2a1f3a3e17ce6c0b8da
Initial Considerations
2^N not to cut, because N is 10^5 or bigger.
Will it be a 2N DP?
(after neg. verb stem) seeming impossible
How about a style that ticks once for maximum length and then moves forward one tick at a time?
Shakitori-legal approach, searching only for likely solutions
I wonder if the lower limit will gradually increase, and if the search space will become rather small because it is not necessary to search for the area where the lower limit becomes smaller than the lower limit.
Official Explanation
To be continued, once I think about it on my own after this.
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