my sensor gives a reading in resistance change. However, I can track that change easily with an amplifier circuit. However, I don't want to use in that way. I want to use my device by multiplying its ...
On the island of knights and knaves (where knights always tell the truth and knaves lie), you meet two islanders named Penny and Quinru.
Penny: Both Quinru and I are knaves!
Who is a knight and who ...
A token starts at location (0,0) on an infinite grid. On turn $n$ it must jump $n$ units horizontally or vertically, in one of four directions. What is the least number of turns needed for it to reach ...
(In German a Jigsaw is simply called Puzzle, the pun is lost in English...)
A jigsaw has to match by form and (mostly!) by color at the tile borders. Assume your basic jigsaw tile consists of $m*m$ ...
Imagine my horror to discover that I'd been betrayed. I knew it was one among five of my most trusted inner circle, so I sent them this message:
Dear Anna, Bess, Chrissy, Diana, and Eva,
I know one ...
You can skip the back story and directly jump to the question.
Capitalism has arrived in suburban Chesster the community most famed for The Game, and with a vengeance. Rents have trebled in less than ...
A humorous king pays his worker with one inch gold bar everyday. He had a $31$ inches gold bar and he paid the worker $31$ days of a month cutting it in just $4$ places. How is this possible?
I came across this sign in a shop and thought it could make a nice puzzle. So you can buy items and get discounts depending on how many items you got. You can combine discounts and use as many as you ...
This is a Sudoku that is also a Brainfuck program.
The standard rules of Sudoku apply. The same symbol can not appear twice in the same row, column, or 3x3 box.
The grid should also form a functioning ...
I come with time
To most, if not all people
Don't forget, you might get me too
I am a very emotional pendulum
And can cause people to go mad
Remember, I'm not uncommon
Tens of millions is my count
These are pentominoes, with letter codes:
Create 4 yes/no questions which uniquely classify each pentomino.
Examples of such questions are:
Does it have rotational symmetry?
Does it have reflection ...
There is a desert which can be crossed only by walking and this takes six days. The explorers of the desert can carry at most four days' water and food. If they want, they can take helpers with them. ...
(Disclaimer: I remember a puzzle like this I did a long time ago, but this isn't a direct copy of the puzzle, only it's formatting. If this is appears to be a copy of another riddle, I will simply say ...
Despite being well-decorated, stylish, and sturdy
I'm often dark inside, and
When put into use, I am dark all around
I am destined to carry Something (that will soon turn foul)
To keep what is inside ...
Here is a puzzle that I recently encountered:
You have a four digit lock with the following clues.
When you enter 1378, one digit is correct and well-placed.
When you enter 2834, nothing is correct.
There are $72$ criminals in a jail in $8$ cells as shown in the picture above. There are $9$ criminals in each cell. There are $4$ guards. Each of them watch over the $4$ corridors. As there is a door ...
I am a cube
Made up of cubes
Twenty six cubes
But always a cube
A large, cubed cube
Not a ruby cube
And not a phoenix cube
But a bright cube
I go into your mouth hard and dry
And I come out limp and moist
I'm often a pinkish color
But of course, my color may differ
As may my size and flavor
Indeed, my very texture might vary
As well as the ...
You were kidnapped and had no way of escape. The kidnapper opens the lights, and in front of you is an opened box of Tic-Tacs. He claims that he ate from 0-5 Tic-Tacs, (with 60 from the newly-bought ...
I have a bow, but no set of strings
I have a collar, but I'm not a pet thing
I have a stem, but I'm not from a pot
I have a blade, just not from Camelot
I am often scraped and dropped and abused
I am present at school
But can't stand pools
Water tends to scare me
But croutons appease me
I frolik in class
But can't ever pass
Work can't be for me
But climbing is my glee
I crow in all lines
I have 4 brothers
My 1st brother is a bother, and points everything out
My 2nd brother is tall, and quite foul at heart.
My 3rd brother is about as tall as my 1st, and quite decorative.
My 4th brother ...
This is a variation on the classic Slitherlink Puzzle. However, instead of creating one loop, you must create 2 separate loops.
The two loops can not share any edges, however they can cross or meet on ...
The fugitive is at the origin. He moves at a speed of 100. You have a guard at every integer coordinate except the origin. A guard's speed is 1. The fugitive and your guards move simultaneously and ...