sithope's blog

468B Two Sets My greedy solution~~
By sithope, 10 years ago, In English

This problem has many ways to solve it,here I want to write something about my greedy solution,thouth I haven't confirm it.

My solution is,firstly,sort the number sequence P，then start from the smallest one (suppose b>a)，if it can be divided into B set with a number which hasn't been used,just put it into B set,otherwise if it can be divided into A set with a number which hasn't been used,just put it into A set,or puts NO and ends the program.

I hope to know someone who has the same idea with me and confirm it and share my solution with you!!!

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10 years ago, # |
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My solution also used 2 sets:

http://codeforces.com/contest/468/submission/7875703

Firstly, put all elements into set A.

Secondly, put elements which are not suitable in set A into set B.

Finally, erase elements x and b-x in set B (or set A) and do some more simple work.

Hope that help you!

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6 years ago, # |
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Your greedy idea is correct and nice. But in CF's tutorial it is mentioned that this problem can be solved by using a 2SAT approach. Does anybody have idea exactly how? Where are the logical variables, where is CNF?

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