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C problem of today's contest, getting negative value even after applying modulo operator
By you_know_wh0, history, 4 years ago, In English

i am getting negative value even after applying %M operation at all steps. i dont understand where i'm doing wrong//i wrote this code for C problem of today's contest-codeforces round #711

my code: my code

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4 years ago, # |
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x=(x+M)%M; this will convert the negative value in to positive. Prove- x= x%M + M%M then M%M=0 so x=x%M;

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    4 years ago, # ^ |
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    yeah, but why i am even getting negative values in the first place. i am computing values in such a way that their range is [0, M].

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      4 years ago, # ^ |
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      pw can overflow, since it can reach (i-1)^1000 and is never modded.

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