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

int main()
{
    // 入力
    unsigned long long A, B, C;
    cin >> A >> B >> C;

    // 二分探索
    unsigned long long left = 0;
    unsigned long long right = C;
    while(right - left > 1)
    {
        unsigned long long mid = (left+right)/2;
        unsigned long long sum = (mid/A)*B + mid-(mid/A);
        if(sum >= C) right = mid;
        else left = mid;
    }

    // 解を出力
    cout << right << endl;
    return 0;
}