#pragma GCC optimize("Ofast")
#include<bits/stdc++.h>
#include<iostream>
#include<cmath>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;


#define mod 1000000007
#define one(x)   __builtin_popcountll(x)
#define zero(x)  __builtin_ctzll(x)
#define pp pair<ll,ll>
#define all(x) (x).begin(), (x).end()
#define removeDuplicates(a) a.resize(unique(all(a))-a.begin())
template<class T> using oset =tree<T, null_type, less<T>, rb_tree_tag,tree_order_statistics_node_update> ;
typedef long long int ll;

const int mxn = 2e6 + 10;

ll b[mxn];
ll a[mxn];
array<ll, 2> arr[mxn];



void subMain(){
    double x, y, z;
    cin >> x >> y >> z;
    //cout<<fixed<<setprecision(6);
    double ans=(y*1.00000)/x;

    ans=ans-0.000010;
    ans*=z;
    cout<<(int)(ans)<<"\n";
}



int main(){

	ios_base::sync_with_stdio(false);
	cin.tie(0); cout.tie(0);


	/*int t, i = 0;
	cin >> t;
	while(t--){
        //cout << "Case #" << i+1 << ": ";
        subMain();
        //i++;
	}*/
	subMain();
	cerr<<"Time : "<<1000*((double)clock())/(double)CLOCKS_PER_SEC<<"ms\n";
	return 0;
}

/* dont stick to an approach */
#include <iostream>
#include <iomanip>
#include <cmath>
#include <string>
#include <algorithm>
#include <list>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <unordered_map>
#include <vector>
#include <numeric>
#include <cstdlib>

using namespace std;

typedef long long ll;
typedef unsigned long long int ull;
typedef long double ldb;

#define PB push_back

#define For(i, n) for (ll i = 0; i < n; i++)

#define trav(a,x) for (auto& a : x)

#define PYES cout<<"YES\n"
#define PNO cout<<"NO\n"
#define PYes cout<<"Yes\n"
#define PNo cout<<"No\n"
#define endl '\n'

#define sq(x)           (x*x)

#define vll             vector<ll>
#define rev(v)          reverse(v.begin(),v.end())
#define srt(v)          sort(v.begin(),v.end())
#define grtsrt(v)       sort(v.begin(),v.end(),greater<int>())
#define mnv(v)          *min_element(v.begin(),v.end())
#define mxv(v)          *max_element(v.begin(),v.end())
#define all(v)          v.begin(),v.end()

#define Fas ios::sync_with_stdio(0), cin.tie(0), cout.tie(0)

//--------------------------------------------functions-------------------------------------------------//

ll power(ll a,ll b){ll result=1;while(b>0){if(b%2 == 1){result *= a;} a *= a;b /= 2;}return result;}
ll gcd(ll x,ll y){ll r;while(y!=0&&(r=x%y)!=0){x=y;y=r;}return y==0?x:y;}
ll countSetBits(ll x){ll Count=0;while(x>0){if(x&1) Count++;x=x>>1;}return Count;}
bool isPerfectSquare(ll n){ll sr = sqrt(n);if (sr * sr == n)return true;else return false;}
ll mod(ll x,ll M){return ((x%M + M)%M);}
ll add(ll a, ll b,ll M){return mod(mod(a,M)+mod(b,M),M);}
ll mul(ll a, ll b,ll M){return mod(mod(a,M)*mod(b,M),M);}
ll powerM(ll a,ll b,ll M){
    ll res=1ll;
    while(b){
        if(b%2ll==1ll){
            res=mul(a,res,M);
        }
        a=mul(a,a,M);b/=2ll;
    }
    return res;
}
//------------------------------------sieve of erantothenes-----------------------------------------------//
//ll MAXN=1e7+100;
//vector<ll> fact(MAXN);
//void sieve_of_erantothenes()
//{
//    fact[1] = 1;
//    for (ll i = 2; i <= MAXN; i++)
//        fact[i] = i;
//    for (ll i = 4; i <= MAXN; i += 2)
//        fact[i] = 2;
//    for (ll i = 3; i * i <= MAXN; i++){
//        if (fact[i] == i){
//            for (ll j = i * i; j <= MAXN; j += i)
//                if (fact[j] == j)
//                    fact[j] = i;
//        }
//    }
//}
//----------------------------------------nCr mod------------------------------------------------------//
ll modInverse(ll n,ll M){
    return powerM(n,M-2,M);
}
ll nCrM(ll n,ll r,ll M){
    if(n<r) return 0;
    if(r==0) return 1;
    vector<ll> fact(n+1);
    fact[0]=1;
    for(ll i=1;i<=n;i++){
        fact[i]=mul(fact[i-1],i,M);
    }
    return mul(mul(fact[n],modInverse(fact[r],M),M),modInverse(fact[n-r],M),M);
}
//-----------------------------------------------solve-----------------------------------------------------//
void solve(){
    ldb x,y,z;cin>>x>>y>>z;
    for(ll i=1000008;i>=0;i--){
        if(x*i<y*z){
            cout<<i<<endl;
            return;
        }
    }
}
 

int main(){
    Fas;

//    freopen("input.txt","r",stdin);
//    freopen("output.txt","w",stdout);

//    ll t=0;
//    cin>>t;
//    while(t--)
        solve();

    return 0;
}

