#include <iostream>
unsigned long long mult(unsigned long long x,unsigned long long y,unsigned long long const z){
	if(y == 1)return x % z;
	else if( y== 0)return 0;
	else if(!(y & 1))return mult((x + x)%z,(y/2) % z,z);
	else return (x % z + mult(x % z,(y - 1) % z,z))%z;
	
}
int main() {
	unsigned long long a,b,c;
	std::cin >> a >> b >> c;
	std::cout << mult(a,b,c);
}