#include <iostream>

using namespace std;

int main()

{

int k, x1, y1, x2, y2, loc = 0;

cin >> k;

cin >> x1 >> y1;

cin >> x2 >> y2;

for (int i = 0; i < 9999; i++)

{

loc += k;

if (loc % x1 == 0)

{

k -= y1;

}

if (loc % x2 == 0)

{

k -= y2;

}

if (k <= 0)

{

cout << loc;

break;

}

}

}