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Looking for efficient algorithm to solve x^y mod z

I am in the middle of coding and suddenly realized that I have to solve (code) x^y mod z, where x, y, and z are large integer numbers. Straight coding, that is by multiplying x by y times before performing mod with z, is inefficient.

I know that I am dealing with big integers, but my interest is in the algorithm. I am reading fast exponentiation right now, but just in case any of you know better algorithms (or libraries). I am using C language, if that's important.

Comments

Anonymous said…
big headache! :D
10:00 PM
website dunia veteriner said…
salam luar biasa .... nice post!
1:38 PM
Rifki said…
Is in C Support big integer ?
as i know, it just support in java.
1:13 PM
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