#include <iostream>
using namespace std;
typedef unsigned long long ull;

int main(void)
{
    ull a,b,p,sum = 0;
    scanf("%lld%lld%lld",&a,&b,&p);
    while (b)
    {
        if (b & 1)  sum = (sum + a) % p;
        a = a * 2 % p;
        b >>= 1;
    }
    printf("%lld",sum);
    return 0;
}