#include <iostream>

using namespace std;

int main() {
    long long a, b, p;
    cin >> a >> b >> p;
    a %= p, b %= p;
    long long temp = a, ans = 0;
    for (; b ; b >>= 1) {
        if (b & 1) ans = (ans + temp) % p;
        temp = (temp + temp) % p; 
    }
    cout << ans % p << endl;
}