Removal of billboards from given ones

Question

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ADZEN is a very popular advertising firm in your city. In every road you can see their advertising billboards. Recentl

Answer 1

soulcheck's (second) DP solution is correct in principle. There are two improvements you can make using these observations:

1) It is unnecessary to allocate the entire DP table. You only ever look at two rows at a time.

2) For each row (the v in P(v, i)), you are only interested in the i's which most increase the max value, which is one more than each i that held the max value in the previous row. Also, i = 1, otherwise you never consider blanks.