Can anyone explain the approach?

Правка en1, от Evan_Shareef, 2021-10-09 10:17:19

I have read the editorial but yet not cleared enough about the approach. Can anyone provide me some hints? How to approach this problem? I just need to know about the observation that how you will approach the problem to solve it.

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en1 Английский Evan_Shareef 2021-10-09 10:17:19 328 Initial revision (published)