For the first several contests, help build tools for the Robonaut R2, a robotic assistant used to help humans work and explore in space. Why not take this chance to be a part of humanity's journey to go …

In order to keep away Trespassers, he decides to Build some Beacons (Towers) on the perimeter of the Island. To build these Beacons, he visits the Mainland to purchase Stone.

SPOJ (Sphere Online Judge) is an online judge system with over 315,000 registered users and over 20000 problems. The solution to problems can be submitted in over 60 languages including C, C++, …

Build exceptional systems With Sphere Engine, you have all the features you need to create your very own systems like SPOJ. It is a unique, powerful technology, tested on more than 300 million …

SPOJ (Sphere Online Judge) is an online judge system with over 315,000 registered users and over 20000 problems. The solution to problems can be submitted in over 60 languages including C, C++, …

You want to build a fence of length L such that the area enclosed between the wall and the fence is maximized. The fence can be of arbitrary shape, but only its two endpoints may touch the wall.

You are living in a city build entirely of power towers such as 3^3^3 and 10^10^10^10. To enter a building you must type the last 9 digits of the number represented by the tower, written in decimal …