#include <bits/stdc++.h>

using namespace std;

typedef unsigned long long ull;

int main() {

ull a, b, p;

cin >> a >> b >> p;

ull res = 0;

while (b) {

if (b & 1) res = (res + a) % p;
	
b >>= 1;
	
a = a * 2 % p;

}

cout << res;

return 0;

}