#include<iostream>
using namespace std;

int main(){

  int a, b, n, sum;
  double c;
  
  while(cint >> a >> b >> n){
    sum = 0;
    c = a / b;
    for(int i=0; i<n; i++, c * 10){
      sum += (int)c % 10;
    }
    
    cout << sum << endl;
  }

  return 0;

}