
White to play and mate in 6. This one is very tough!
Very hard brain teasers and puzzles
White to play and mate in 6. This one is very tough!
Can you figure out the number I am thinking of?
Some cryptic clues:
If you have all the answers right, that’s only about 33% percent of the solution: you need to justify them too.
Some clues were left over, so here’s a second set:
An ingenious and very difficult puzzle by Bass on Puzzling StackExchange (spoiler warning: contains the solution)
In this maze of 8×8 rooms, each room has an arrow that points up, down, left, or right – and it will only let you move to the adjacent room in the direction of the arrow.
After you leave a room, or if you are unable to move because there is no adjacent room in the direction of the arrow (i.e., the arrow points outside the maze but there is no exit), the arrow in that room will rotate 90 degrees clockwise.
You start in the bottom left room, and the only exit is the right door in the top-right room.
Prove that no matter what the initial arrangement is, you will eventually escape the maze.
After the results of an election, you are told that one candidate has received the majority of the votes, but you don’t know which candidate. You have exactly one opportunity to hear the votes, but:
Given these restrictions, is there a way figure out which candidate received the majority of votes?