import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
//n盒牛奶
int n = scanner.nextInt();
//h分钟能喝完
int h = scanner.nextInt();
//m分钟后还有多少牛奶
int m = scanner.nextInt();
if(m % h == 0) {
System.out.println(n - (m / h));
} else {
System.out.println(n - (m / h + 1));
}
}
}