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Doubt in the Codeforces(918) Div4-C problem
By Sujay_27, history, 10 months ago, In English

Hello folks, Need some help in debugging.. The question is on the right : Ques This is the code I submitted : Code I don't know why I'm getting signed integer overflow, inspite of having all the variables as long long. Can someone enlighten me on what I'm missing. [contest:918][problem:1915C]

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10 months ago, # |
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Auto comment: topic has been updated by Sujay_27 (previous revision, new revision, compare).

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10 months ago, # |
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Sum can be 1e14 which would lead to overflow you can set a upperlimit of 1e9

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10 months ago, # |
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The maximum value that a long long variable can have is $$$2^{63} - 1$$$. In your code sum can be equal to $$$2 \cdot 10^{14}$$$ in some test cases and thus mid * mid may get bigger than the long long limit.

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10 months ago, # |
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In worst case, the sum can be 2*10^14 then the mid will be 10^14. mid * mid will be 10^28. long long can hold at most 10^18.

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10 months ago, # |
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instead of binary search,why arent you using sqrt its much simpler code

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    10 months ago, # ^ |
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    yea I figured that, but wanted to try with binary search

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10 months ago, # |
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it works if you use unsigned long long instead of signed long long (long long)

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    10 months ago, # ^ |
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    Oh ok

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    10 months ago, # ^ |
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    nah mate, unsigned long long only goes up to about 1.84*10^19, which is still nowhere near 10^28.

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