学步园

#include<iostream>
#define ll unsigned long long
using namespace std;
ll a,b,p;
ll mult(ll t,ll k){
	ll f=0;
	for(;k;k>>=1,t=(t+t)%p)if(k&1)f=(f+t)%p;
	return f;
}
int main(){
	cin>>a>>b>>p;
	cout<<mult(a,b);
	return 0;
}