Raising large number to large power and mod it by a large number?

Question

I am stuck with probably simple question. I got 3 large numbers(A,B,C), all integers and i need to do the following: power A to B and modulo the result by C, and then check if t

Answer 1

try this approach

double a,b,c;

a = 1124124124254234;
b = 1124124124254234 * 5;
c = 1124124124254234 * 2;

double power = pow(a,b); 

double mod = fmod(power, c);

if (mod != 1){
    printf("Something!\n");
}