dp on trees help , csacademy .

Revision en1, by mokoto, 2019-02-21 13:41:51

in the problem sugarel and love , how to choose two sons such that we can maximize

DP[i][1]={max(DP[j][0]+v[i][j]+DP[t][0]+v[i][t])∣ where j and t are sons of i}. For all other sons, we add max(DP[j][0],DP[j][1],DP[j][2]) as given in editorial [](https://csacademy.com/contest/fii-code-2019-round-1/task/Sugarel-in-Love/solution/) since there can be nC2 choices time complexity would be O(n2) , how to do it in O(n) time .

i think we can choose first two sums which gives max(DP[j][0]+v[i][j]+DP[t][0]+v[i][t]) as it will not always optimal .

any idea.

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  Rev. Lang. By When Δ Comment
en3 English mokoto 2019-02-21 13:42:47 1 Tiny change: 'ink we can choose fi' -> 'ink we cant choose fi'
en2 English mokoto 2019-02-21 13:42:21 86
en1 English mokoto 2019-02-21 13:41:51 770 Initial revision (published)