#include<iostream>
#include<string>
#include<vector>
#include<cstdio>
#include<sstream>
#include<algorithm>
#include<cmath>
#include<map>
#include<functional>
using namespace std;
int stoi(string x){stringstream ss;ss<<x;int tmp;ss>>tmp;return tmp;}
string itos(long double x){stringstream ss;ss<<x;return ss.str();}
int main(){
long double a,b;
long double x;
int n;
string tmp;
int sum=0;
while(cin>>a>>b>>n){
sum=0;
x=a/b;
x-=(int)((a/b));
tmp=itos(x);
for(int i=0;i<10000;i++)tmp=tmp+"0";
for(int i=2;i<n+2;i++){
	string v;
	v.clear();
	v.push_back(tmp[i]);
	sum+=stoi(v);
}
cout<<sum<<endl;
}
return 0;
}