#include <bits/stdc++.h>
using namespace std;

using ll = long long;
#define rep(i, j) for(int i=0; i < (int)(j); i++)

template<class T> bool set_min(T &a, const T &b) { return a > b  ? a = b, true : false; }

const ll INFL = 1LL << 60;

template<typename T>
T gcd(T a,T b){
    T c=a,d=b,r;
    do{r=c%d;c=d;d=r;}while(r);
    return c;
}

template<typename T>
T lcm(T a,T b){return a*b/gcd(a,b);}

class Solver {
  public:

    ll trial(ll A, ll B, ll T) {
        ll mini = INFL;        
        rep(k, 2) {
            if(k != 0) swap(A, B);
            rep(i, 10000000) {
                if(A * i >= T) {
                    set_min(mini, A * i);
                } else {                
                    ll j = (T - A * i) / B;                
                    while(A * i + B * j < T) j++;                
                    set_min(mini, A * i + B * j);
                }
            }
        }
        return mini;
    }
    
    bool solve() {
        ll A, B, T; cin >> A >> B >> T;
        ll ans = 0;

        ans += (T / (A * B)) * A * B;
        T %= A * B;

        cout << ans + trial(A, B, T) << endl;
        
        return 0;
    }
};

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    Solver s;
    s.solve();
    return 0;
}