#include <iostream>
using namespace std;
int main(){
	int a,b,n;
	while(cin>>a>>b>>n){
		long double d=a/(double)b;
		int sum=0;
		if(d>1){
			int x=d;
			d -= x;
		}
		for(int i=0;i<n;i++){
			int x=d*10;
			sum += x;
			d = d*10-x;
		}
		cout<<sum<<endl;
	}
	return 0;
}