#include <bits/stdc++.h>
using namespace std;
#define _GLIBCXX_DEBUG
#define rep(i, n) for (ll i = 0; i < (ll)(n); i++)
#define repx(i, x, n) for (ll i = (ll)(x); i < (ll)(n); i++)
#define repr(i, n) for (ll i = ((ll)(n)-1); i >= 0; i--)
#define reprx(i, x, n) for (ll i = ((ll)(n)-1); i >= (ll)(x); i--)
#define all(x) (x).begin(),(x).end()
#define sz(x) ((ll)(x).size())
#define submit(x) {cout<<x<<endl; return 0;}
#define X first
#define Y second
template<class T> using V = vector<T>;
template<class T> using VV = V<V<T>>;
template<class T>bool chmax(T &a,T b) {if (a<b) {a=b; return 1;} return 0;}
template<class T>bool chmin(T &a,T b) {if (b<a) {a=b; return 1;} return 0;}
template<class T>long long ip(T a, T b) {bitset<60> s(b); long long val=1; for(int i=0;i<60;i++){if(s.test(i))val*=a; a*=a;} return val;}
using ll = long long;
using P = pair<ll, ll>;
const ll INF = 1LL << 60;
const double PI = 3.1415926535897932;

int main() {
  double x,y,z;
  cin>>x>>y>>z;
  double price = y / x;
  double ans = z * price;
  ll ans2 = ans;
  if (ans2 - ans == 0) ans2--;
  submit(ans2)
}

#include <iostream>
#include <fstream>
#include <iomanip>
#include <math.h>
#include <limits.h>
#include <algorithm>
#include <functional>
#include <vector>
#include <list>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <bitset>
#include <string>
#include <string.h>
#include <sstream>
#include <ctime>

using namespace std;

#define eps 1e-12
#define pi 3.14159265358979323846
#define pb push_back
#define mp make_pair
#define st first
#define nd second
#define bgn begin
#define ll long long
#define ld long double
#define ull unsigned long long
#define ii pair<ll,ll>












int x, y, z;


void solve()
{
	cin >> x >> y >> z;
	for(int i = 0;; i++)
	{
		if(x*i >= z*y)
		{
			cout << i - 1 << "\n";
			return;
		}
	}
}

int main()
{
	std::ios::sync_with_stdio(0);
	cin.tie(0);
#ifdef localProject
	freopen("in.txt", "r", stdin);
#endif
	solve();
	return 0;
}