#include<bits/stdc++.h>
typedef long long ll;
using namespace std;
ll INF = 1LL << 61;
int MOD = 1e9+7;
main(){
    ll A,B,C;
    cin >> A >> B >> C;
    //n歳のとき n + floor(n/A) * B - floor(n/A)
    ll ok = INF,ng = 0;
    while(abs(ok - ng) > 1){
        ll mid = (ok + ng) / 2;
        ll flo = mid / A;
        if(mid + flo * (B - 1) >= C)ok = mid;
        else                   ng = mid;
    }
    cout << ok << endl;
}