#include <iostream>
using namespace std;

int mulMod (int a, int b, int m) {
    int res = 0;
    for ( ; b > 0; b >>= 1) {
        if (b & 1)
            res = (res + a) % m;
        a = (a + a) % m;
    }
    return res;
}

int main () {
    int a, b, m;
    cin >> a >> b >> m;
    cout << mulMod (a, b, m) << endl;
    return 0;
}