993 992 991
 100 1 10
 960 935 994
 99 8 99
 60 16 1
 759 10 258
 24 19 9
 196 169 144
 1000 999 1
 945 812 917
 1000 100 10
 500 300 300
 888 777 1000
 2 1 4
 24 12 12
 767 2 514
 2 1 2
 1000 1 1
 5 2 1
 70 32 1
 765 123 899
 17 7 10
 5 4 10
 888 777 888
 66 38 4
 1000 999 1000
 9 3 300
 244 87 4
 765 123 45
 1000 1 1000
 305 203 421
 100 10 1
 64 12 8
 894 1 999
 2 1 1
 18 14 10
 6 2 4
 888 777 1
 27 26 1
 2 1 3
 5 1 5
 7 3 200
 561 31 917
 17 10 7
 93 74 831

1
 990
 27
 1127
 3
 19325
 3
 24
 1
 151
 90
 200
 143
 4
 12
 196605
 2
 999
 2
 2
 4693
 15
 3
 127
 3
 2
 600
 8
 235
 999000
 212
 9
 35
 892107
 1
 3
 8
 1
 1
 3
 20
 267
 15678
 5
 214


import java.util.*;

public class Program
{
	public static void main(String[] args)
	{ 
		Scanner s = new Scanner(System.in);
		int a,b,c,t = 0, t0 = 0;
		boolean espera = true;
		//Console.WriteLine("Digite o tamanho dos dados/s do video :  ");
		a = s.nextInt();;
		//Console.WriteLine("Digite a capacidade de dowload de dados/s :  ");
		b = s.nextInt();;
		//Console.WriteLine("Digite o tamanho do video em segundos :  ");
		c = s.nextInt();;
		//System.out.println(a + " " + b + " " + c);

		while ( a * c > t* b ) //while (a * c > t * b)
            {
                //Console.WriteLine("tempo:" + t);

                for (t0 = 1; t0 <= t ; t0++)
                {
                   
                    if ((t0)*b >= (a * c)-(t*b) && t0+t<=t+c && espera)
                    {
                        System.out.println(t0);
                       
                        t0 = t + 1;
                        espera = false;
                        
                    }
                }
                t++;
                

            }
		

	

	}


}