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getting time limit exceeded on SPOJ "MCOINS — Coins Game" problem.pls someone help me.
By mahim007, history, 11 years ago, In English

problem link->MCOINS — Coins Game

my code-> codepad

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11 years ago, hide # |
 
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Your solution has complexity of O(N) per single tower, which results in O(m*N) per test-case which unfortunately is not fast enough. One could easily notice, however, that the dp states will be the same for the same K and L and are independent of N, so you can compute the states only for the largest tower (biggest N), thus resulting in O(N) per test-case.

I managed to get AC modifying your code to do just that, so feel free to ask any questions :)

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    11 years ago, hide # ^ |
     
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    sorry for my late reply. would u kindly describe the way more elaborately?? since i am new to dp i find it difficult :( any clue,hints,idea will be greatly appreciated :)

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      11 years ago, hide # ^ |
       
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      Well let's consider the example. We have :

      2 3 5 
3 12 113 25714 88888

      So what your solution will do is calculate the states from 1 to 3, then from 1 to 12, then from 1 to 113, then from 1 to 25714, then from 1 to 88888. However you can instead calculate them just once from 1 to 88888 and then use dp[3], dp[12], dp[113], dp[25714] and dp[88888] to answer your queries. Do you understand what I mean?

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        11 years ago, hide # ^ |
         
        Vote: I like it +13 Vote: I do not like it

        yes Enchom bro,i completely understand your idea.even if i never understand a problem so well before :D i implement as you said and got accepted :) :) thank u so much.

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11 years ago, hide # |
 
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hey.. can you please give me any hints on writing a recursive solution to this problem.. I would be so grateful if you do :D

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