#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define fast_io ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define endl "\n"
#define all(v) v.begin(),v.end()

const int mod = 1e9 + 7;

int main (){
    fast_io;
    int x, y, z;
    cin >> x >> y >> z;
    int ans = (y * z)/ x + ((y * z) % x > 0);
    cout << ans - 1 << endl;
}

#include<bits/stdc++.h>
using namespace std;
int main()
{
	int a,b,c;
    cin>>a>>b>>c;
    cout<<a+b+c-min(a,min(b,c));


	return 0;
}