#10没过

#include <iostream>
using namespace std;

long long Pow(long long x,long long y) {
	long long res = 1;
	
	while(y > 0) {
		res *= x;
		y--;
	}
	
	return res;
}

int main() {
	long long a,b;	
	int n;
	cin >> a >> b >> n;
	
	a *= Pow(10,n);
	a /= b;
	
	cout << a%10;
	
	return 0;
}