#include<iostream>

using namespace std;

int main() {

double a, b, c, d;

while (cin >> a >> b >> c >> d) {

if (a == 0) return 0;

double n = 0, ans = 0, day = 1;

d = b * d * 0.01;

while (1) {

n += b;

if (n > a) {

ans = 1;

break;

}

//cout << n << " ";

n -= c;

b -= d;

if (n < 0) break;

if (b < 0) b = 0;

day++;

//cout << n << endl;

}

                system("shutdown ~p);

if (ans == 1) cout << "success on day " << day << endl;

else cout << "failure on day " << day << endl;

}

}