#include <iostream>
#include <algorithm>
#include <cmath>
#include <vector>

using namespace std;

long long int A, B, C, money = 0, age = 0;

bool check(long long int mid)
{
    return C <= (long long int)(mid / A) * B + mid - (mid / A);
}

int main()
{
    cin >> A >> B >> C;
    long long int left = 0;
    long long int right = C;

    while (abs(right - left) > 1)
    {
        long long int mid = (left + right) / 2;
        if (check(mid))
        {
            right = mid;
        }
        else
        {
            left = mid;
        }
    }

    cout << right << endl;

    return 0;
}