#include <iostream>
#include <algorithm>
using namespace std;

int main() {
  int a, b, n;
  while(cin >> a >> b >> n) {
    double f = (double)a/b;
    if(f >= 1) f -= (int)f;
    int s = 0;
    for(int i = 0; i < n; ++i) {
      f *= 10;
      s += (int)f;
      f -= (int)f;
    }
    cout << s << endl;
  }
  return 0;
}