#include <bits/stdc++.h>

using namespace std;

namespace {

    typedef double real;
    typedef long long ll;

    template<class T> ostream& operator<<(ostream& os, const vector<T>& vs) {
        if (vs.empty()) return os << "[]";
        auto i = vs.begin();
        os << "[" << *i;
        for (++i; i != vs.end(); ++i) os << " " << *i;
        return os << "]";
    }
    template<class T> istream& operator>>(istream& is, vector<T>& vs) {
        for (auto it = vs.begin(); it != vs.end(); it++) is >> *it;
        return is;
    }

    ll A, B, T;
    void input() {
        cin >> A >> B >> T;
    }

    ll next(ll r) {
        ll d = B % A;
        ll ans = r - d;
        if (ans < 0) ans += A;
        return ans;
    }

    void solve() {
        ll r = T % A;
        if (r == 0) {
            cout << T << endl;
            return;
        }
        ll b_count = 0;
        vector<bool> found(A, false);
        found[r] = true;
        for (int i = 0; i < A; i++) {
            //cerr << "r: " << r << endl;
            r = next(r);
            if (r == 0) {
                cout << T << endl;
                return;
            }
            b_count++;
            if (B * b_count > T) break;
            found[r] = true;
        }
        for (int i = A - 1; i >= 0; i--) {
            if (found[i]) {
                cout << T + A - i << endl;
                return;
            }
        }
    }
}

int main() {
    input(); solve();
    return 0;
}