Help in Atcoder regular contest 066 problem B, Xor Sum.

Revision en2, by spirited_away_, 2019-06-21 01:01:22

Given a number N, The problem asks you to find all such pairs u,v such that there exists another set of pairs a,b such that 1. a ^ b = u

  1. a + b = v

where u , v <= N.

I finally concluded that basically we have to find a+b<=N, but how to proceed from here. Many other submissions used dp approach to solve this problem. Can anyone tell me the approach and intutition to solve it. Editorial is in japanese.

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  Rev. Lang. By When Δ Comment
en4 English spirited_away_ 2019-06-21 01:23:43 134
en3 English spirited_away_ 2019-06-21 01:01:59 2 Tiny change: 'uch that\n1. a ^ b' -> 'uch that\n\n1. a ^ b'
en2 English spirited_away_ 2019-06-21 01:01:22 6 Tiny change: '(https://abc050.contest.a' -> '(https://arc066.contest.a'
en1 English spirited_away_ 2019-06-21 01:00:46 531 Initial revision (published)