#include <iostream>
#include <vector>
#include <algorithm>
#define _LIBCPP_DEBUG 0 // clang
// #define _GLIBCXX_DEBUG // gcc
using namespace std;
using ll = long long;

int main()
{
    int x, y, z;
    cin >> x >> y >> z;

    int res = (y * z - 1) / x;

    cout << res << '\n';
    
    return 0;
}

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using pll = pair<ll,ll>;
using pld = pair<ld,ld>;
using vll = vector<ll>;
using vld = vector<ld>;
using vstr = vector<string>;
#define _GLIBCXX_DEBUG
#define rep(j, m) for (ll j = 0; j < (ll)(m); j++)
#define rep2(i, l, n) for (ll i = l; i < (ll)(n); i++)
#define all(v) v.begin(), v.end()
const ld PI = 3.1415926535897932;
const ll MOD = 1000000007;
const ll MOD2 = 998244353;
vll dx = {-1,0,1,0};
vll dy = {0,-1,0,1};
vll Dx = {-1,-1,-1,0,0,1,1,1};
vll Dy = {-1,0,1,-1,1,-1,0,1};
const ll INF = 1000000000000000;


int main() {
    ll X,Y,Z;
    cin >> X >> Y >> Z;
    cout << Z*Y/X - (1 - min(1LL,Z*Y%X)) << endl;
}