Hi Everyone.
Now I'm wondering about how to count (a*b) % c? 1 <= a,b,c <=10^18.
Any advice?
Thank you.
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Hi Everyone.
Now I'm wondering about how to count (a*b) % c? 1 <= a,b,c <=10^18.
Any advice?
Thank you.
Name |
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You can check if your judge allows int128
You can write your own int128 class (it's a lot easier than general bignum). It's harder than 3. but faster.
You can use algorithm similar to fast exponentiation. Instead of a*a*a*...*a (b times) you calculate a+a+a+...+a (b times) so just change * to + in your favorite quick power implementation.
"Binary multiply" O(log(min(a, b))) :
code