Solving the 8 Queens puzzle with bit operations

The 8 queens puzzle is a classic (and quite fun to solve) toy problem: place eight queens on a chess board in such a way that all queens could fully move without being obstructed by any other queen. While without practical applications, it illustrates a number of aspects of designing algorithms and implementing programmes: - … Continue reading Solving the 8 Queens puzzle with bit operations

Stateless user sessions with encrypted session IDs

When trying to design for stateless services one finds it easy to reduce the information stored in an http session but for one piece: whether the client has authenticated against the server or not. Usually you would implement a proccess for authenticating like this: Client submits credentials (login / password) to the server Server checks … Continue reading Stateless user sessions with encrypted session IDs