How to solve these problems from Google Online challenge?

Revision en1, by pretending, 2021-07-21 23:16:22

These problems were asked in Google Online Challenge a few weeks ago. For first one, I tried to put alternating levels into separate groups (forming only two groups) but that didn't worked for me :(. For second one, I have no idea. I will greatly appreciate any help. Thanks in advance.


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en1 English pretending 2021-07-21 23:16:22 429 Initial revision (published)