using System.Numerics;

public class Program
{
    public static void Main()
    {

        //int num = int.Parse(Console.ReadLine() ?? string.Empty);
        string[] str = (Console.ReadLine() ?? string.Empty).Trim().Split(' ');
        //string str = Console.ReadLine() ?? string.Empty;

        
        int a =int.Parse(str[0]);
        int b =int.Parse(str[1]);
        int x =int.Parse(str[2]);

        int cost = 0;
        int n = 0;
        while(n < x)
        {
            n += a;
            cost += b;
        }
        Console.WriteLine(cost);

    }
}