Duty Rotation Convergence

In a semester there are $n$ daily duty monitors ((\textit{(D)})) which rotate cyclically, and among them student A holds the (m)th position. In addition, there are $p$ weekly duty monitors ((\textit{(W)})) rotating week by week, with student B being the (q)th in order. The semester is organized in weeks with 5 working days and 2 rest days (holidays are ignored), and the order of rotation is never changed. The daily duty monitor is chosen on each working day in a cyclic order (i.e. the schedule repeats every $n$ duty assignments) and the weekly duty monitor is assigned once per week (the schedule repeats every $p$ weeks).

On the (i)th working day of the semester (with (i \ge 1)), the duty monitor is given by [ D(i)=((i-1)\bmod n)+1, ] and for the week number (w=\lfloor(i-1)/5\rfloor+1) the weekly duty monitor is [ W(w)=((w-1)\bmod p)+1. ]

Your task is to determine the first working day (i.e. the smallest positive integer (i)) on which student A is the daily duty monitor and simultaneously student B is the weekly duty monitor. If no such day exists, output exactly Orz mgh!!!.

inputFormat

The input consists of four space-separated integers: (n), (m), (p), and (q), representing the total number of daily duty monitors, the position of A among them, the total number of weekly duty monitors, and the position of B among them respectively.

outputFormat

Output a single line containing the first working day number (i.e. (i)) on which student A and student B are on duty simultaneously. If no such day exists, output Orz mgh!!!.

sample

6 3 4 2

9