P2660 zzc Farming

Maybe in the future zzc will go farming.

The field is a huge rectangle. However, zzc can plant only one square at a time, and the stamina cost for planting a square is the square’s perimeter. Areas that have already been planted cannot be planted again. zzc is lazy and wants to save stamina to hang out with girls, so he wants to finish planting the entire field with the least stamina. Find the minimum stamina cost.

Two positive integers $x, y$, representing the length and width of the field.

Output the minimum stamina cost.

Constraints: $1 \le x, y \le 10^{16}$. Translated by ChatGPT 5