simple puzzle

There are intuitive problems, just apply a common calculation to find the answer, but on the contrary, many problems ask trick questions, making many people unable to think of the

Today, we come to a puzzle that is storming the world's forums these days: classic puzzle puzzle.

In this world, there are puzzles that are simple enough to be solved in 5 minutes, but complex enough for you to grind your teeth for hours and hours without solving.