msatanzeel's blog

Getting TLE despite of O(n) time complexity
By msatanzeel, history, 3 years ago, In English

Today there was Google's Kickstart round H and I have a doubt in the question 3 of it, here's that link to the problem , I have solved this using a doubly linked list data structure for efficient replacements and anyone can easily analyze that over all time time complexity is O(n) , here's is the link to my code.Can someone please tell the reason for the TLE over large inputs..

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3 years ago, # |
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It can't hurt to try fast IO.

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3 years ago, # |
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Have you tried to replace unordered_set with set? unordered_set is unreliable and hackable.

UPD. unordered_map too.

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    3 years ago, # ^ |
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    Yeah, first I used ordered, but then I thought the TLE would be because of the extra logn factor ,so I switched to unordered ones

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3 years ago, # |
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As a start: you're iterating through the entire list every time you check its length.

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    3 years ago, # ^ |
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    Yeah, maybe this can be the issue ,I have not considered as a major draw back, but as you said this can cause TLE ,I will try it to optimize this and update again ,thankyou

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    3 years ago, # ^ |
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    Hey, it worked, thankyou soo much, here is the code

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