#include <iostream>
using namespace std;
typedef unsigned long long ULL;
int main(){
ULL a,b,p;
cin >> a >> b >> p;
ULL res = 0;
while(a){
if(a & 1){
res = (res + b) % p;
}
b = (b + b) % p;
a >>= 1;
}
cout << res << endl;
return 0;
}