K.cpp

#include <bits/stdc++.h>

#define FOR(i,a,b) for(int i=(a),_b=(b); i<=_b; i++)
#define FORD(i,a,b) for(int i=(a),_b=(b); i>=_b; i--)
#define REP(i,a) for(int i=0,_a=(a); i<_a; i++)
#define EACH(it,a) for(__typeof(a.begin()) it = a.begin(); it != a.end(); ++it)

#define DEBUG(x) { cout << #x << " = "; cout << (x) << endl; }
#define PR(a,n) { cout << #a << " = "; FOR(_,1,n) cout << a[_] << ' '; cout << endl; }
#define PR0(a,n) { cout << #a << " = "; REP(_,n) cout << a[_] << ' '; cout << endl; }

#define sqr(x) ((x) * (x))
#define ll long long
using namespace std;

int main() {
    ios :: sync_with_stdio(false);
    double a, b, p;
    while (cin >> a >> b >> p) {
        ll left = 1, right = 1e18;
        ll res = right;
        while (left <= right) {
            ll mid = (left + right) / 2;
            if (a*pow(mid, 1.0 / 3) + b*pow(mid, 0.5) >= p - 1e-9) {
                res = mid;
                right = mid - 1;
            }
            else left = mid + 1;
        }
        cout << res << endl;
    }
}