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

int main()
{
  int a, b;
  int n;

  while (~scanf("%d%d%d", &a, &b, &n)){
    int s = 0;
    for (int i = 0; i < n; i++){
      a *= 10;
      s += (a / b) % 10;
      a %= b;
    }
    printf("%d\n", s);
  }

  return (0);
}