Optical illusions are visual puzzles that are designed in such a way that they can cause the brain to interpret what it sees differently from physical reality. These illusions don't mean that there is ...

A BitSet (also called Bitmap or bit vector) is an ideal data structure to implement a set when values being stored are reasonably small integers. It can be orders of magnitude faster than a generic ...

Test your observation skills with this inverted 36 number brain teaser. Among the repeated numbers, there is odd number hidden. Can you find them within 17 seconds? This puzzle helps improve focus, ...