#include <bits/stdc++.h>

using namespace std;
typedef long long LL;
typedef __int128 LLL;
//long long 存不下怎么办？用 __int128！

LL mul(LLL a, LLL b, LLL p){
    return (a * b) % p;
}

int main()
{
    LL a, b, p;
    cin >> a >> b >> p;
    cout << mul(a, b, p) << '\n';
    return 0;
}