#include #define ll long long #define INF 1000000005 #define MOD 1000000007 #define EPS 1e-10 #define rep(i,n) for(int i=0;i<(int)n;++i) #define each(a,b) for(auto (a): (b)) #define all(v) (v).begin(),(v).end() #define zip(v) sort(all(v)),v.erase(unique(all(v)),v.end()) #define fi first #define se second #define pb push_back #define show(x) cout<<#x<<" = "<<(x)<P; const int MAX_N = 100005; ll gcd(ll a,ll b) { if(a % b == 0){ return b; }else{ return gcd(b,a%b); } } ll lcm(ll a,ll b) { return a / gcd(a,b) * b; } int main() { cin.tie(0); ios::sync_with_stdio(false); ll a,b,t; cin >> b >> a >> t; ll l = lcm(a,b); ll ans = (1LL << 60); for(ll i=0;i < min(b,l/a);i++){ ll hoge = t - i*a; ll cnt = (hoge + b - 1) / b; ans = min(ans,i*a + cnt*b); } cout << ans << endl; return 0; }