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Top Questions

4 votes
0 answers
52 views

The shortest way from A1 to B1

0 votes
2 answers
104 views

Weighing Coins -- a Different Approach

8 votes
0 answers
151 views

Something above

4 votes
1 answer
311 views

Largest prime number erroneously erased when finding all primes less than 1000

2 votes
1 answer
181 views

Hold out to the bitter end

-2 votes
1 answer
82 views

Can you use triangular tiles to form a rectangle of size 2016 cm by 2021 cm?

3 votes
1 answer
310 views

5 guards, and get rid of the timer!

11 votes
5 answers
11k views

IQ test question - 3x3 grids with some shaded cells

2 votes
0 answers
58 views

Whose turn is it?

2 votes
1 answer
98 views

Circular Hedge Maze

14 votes
4 answers
924 views

What is the maximum number of people who speak only 1 language?

0 votes
0 answers
70 views

In the rims of hell, A river flows

10 votes
2 answers
462 views

Is it possible to have a double miracle Sudoku grid?

6 votes
0 answers
281 views

"Many tries will turn failures Ƨ successes"

5 votes
1 answer
284 views

Swap the positions of the 4 chess knights

3 votes
2 answers
5k views

A 10-letter word puzzle - what am I?

7 votes
3 answers
1k views

Green Eyed Oracle Variant - Not a Multiple of 17

0 votes
0 answers
174 views

Alternate 100 Blue Eyed Islanders Riddle Conclusion - Contradictory Laws

10 votes
1 answer
409 views

"Shining Composer"

3 votes
3 answers
549 views

Knights, Knaves, and Spies

6 votes
2 answers
745 views

What is a Pisa Word™?

0 votes
1 answer
80 views

Identify the truth teller, the liar and the spy

6 votes
1 answer
437 views

Can You Find a Tower of Hanoi Word?

10 votes
1 answer
1k views

What is a Flipped Word™?

6 votes
1 answer
688 views

What is a Japanese Word™?

7 votes
1 answer
492 views

A Professor's Presentation

5 votes
2 answers
455 views

Can white checkmate in 1 move?

6 votes
1 answer
614 views

Determine if N is zibbable [closed]

6 votes
1 answer
355 views

Impressions – a cryptic crossword

7 votes
1 answer
362 views

Colombian Sudoku, Cows and Bulls again…

4 votes
2 answers
474 views

Maximizing row and column products in a 4x4 grid

30 votes
1 answer
4k views

Are you radical enough to solve this SURDOKU?

17 votes
1 answer
1k views

Just the two of us

11 votes
2 answers
2k views

Signature doughnut from a city

-3 votes
0 answers
120 views

Are the Polybius cipher and the Bifid cipher really easy to solve?

13 votes
2 answers
550 views

Getting rid of all chess pieces (except the kings) in a sequence consisting only of captures

1 vote
0 answers
91 views

Can black and white cooperatively put a stalemate to black in 16 moves (under ser-h conditions)?

13 votes
4 answers
3k views

The knight's game

8 votes
1 answer
403 views
+500

V.I.P. Club for Stars

3 votes
0 answers
266 views

Mysterious Figure [closed]

5 votes
1 answer
577 views

What were the last three single moves?

17 votes
1 answer
1k views

Can White still castle? #2

13 votes
2 answers
473 views

Can you solve the fates of the missing chess pieces?

8 votes
1 answer
309 views

Rectangular representation (ignore the nonsense)

2 votes
1 answer
275 views

Find the missing animal


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