#include<bits/stdc++.h>
#include
#include
#include
#include
#include
#include
#define ll long long
using namespace std;
const int N=1e5+10;
const int M=2023;
const int inf=0x3f3f3f3f;
double x,y,n;
int main()
{
cin>>x>>y>>n;
cout<<floor(x*n/y);
return 0;
}