#include<iostream>
#include<fstream>
#include<sstream>
#include<cstdio>
#include<vector>
#include<list>
#include<stack>
#include<queue>
#include<deque>
#include<map>
#include<set>
#include<algorithm>
#include<cmath>
#include<string>
#include<cstring>
#include<cstdlib>
#include<climits>
#include<utility>
#include<cctype>
using namespace std;

#define ull unsigned long long
#define ll long long
#define rep(i,j) for(int i=0;i<j;++i)
#define loop(i,a,j) for(int i=a;i<j;++i)
#define mpi(it,table,T,E) for(map<T,E>::iterator it = table.begin();it!=table.end();++it)
#define PI 3.141592654
/*
ifstream fin("input.txt");
ofstream fout("output.txt");
#define cin fin
#define cout fout
*/


int main(){
	int a,b,n;
	while(scanf("%d %d %d",&a,&b,&n) != EOF){
		int r = 0;
		double frac = 1.0*a/b;
		rep(i,n){
			frac = frac - (int)frac;
			frac *= 10;
			r += (int)frac;
		}
		printf("%d\n",r);
	}	
	return 0;
}