#include <iostream>

using namespace std;

int main(int argc, char **argv)
{
	double a, b, tmp;
	int n, sum;
	
	while(cin >> a >> b >> n){
		sum = 0;
		tmp = a / b;
		while(tmp > 1.0){
			tmp -= 1.0;
		}
		for(int i = 0; i < n; i++){
			tmp *= 10;
			sum += (int)tmp;
			tmp -= (int)tmp;
		}
		
		cout << sum << endl;
	}
	
	return 0;
}