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Question in dp problem http://codeforces.net/problemset/problem/478/D

By purple_dreams, history, 7 years ago, In English

This problem has a dp solution. DP table can be dp[900][200000] so that is MLE. But there is an observation that level i depends only on level i-1 so dp[2][200000] is sufficient. My question is how to implement this in top down approach with memoization. Is it possible in such questions to write a top down approach or we have to go with bottom up. Thank you.

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7 years ago, # |
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Yes, bottom up is necessary in this case. This is one of the drawbacks of Top down with memoization approach.

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    7 years ago, # ^ |
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    Thank you. I always find top down with memoization a bit more easy. So i was thinking if that is possible in such cases. But now I will see the bottom up approach. Thanks.

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