Blind man's cards (solution)

The probability of success is 100%. Hard to believe? Here's how.

Blind man's cards

You are in a dark room. On the table there are 9 cards. Exactly 4 of the cards are face down.

Your task is to divide them into 2 stacks. Each stack must have exactly 2 face down cards. What strategy has the largest chance of achieving the goal?

Remember: the room is pitch black, and you cannot see the cards (but of course you can feel them).

Seven Trophies (Solution)

In case you missed the question, here is the link. With a little patience and systematic approach, the answer is pretty straightforward.

Seven Trophies

Alice, Bob, and Charlie participated in a sports tournament. Each won at least 1 trophy. They gave the following statements:

Alice: Bob won more trophies than Charlie.
Bob: Charlie won more trophies than Alice.
Charlie: I love sports!

A truth-telling observer noted that only those who won more than 1 trophy told the truth. He also noted that the three participants won a total of 7 trophies.

Can you deduce who is the liar? Or did they all tell the truth? How many trophies did each of them win?

Recommended read: The Murder of Roger Ackroyd

There was once a time when fictional detectives solve crimes not by relying on DNA matches and forensic evidence, but on the good old "little grey cells". Granted, there is always the scrap of torn clothing, the piece of furniture out of place, and that mysterious phone call - clues that make the Golden Age of Detective Fiction truly enjoyable.

Fancy a different kind of chess?

Try this: Colamone (I think that's what it's called).

Short and simple platformer

Every once in a while we have to try out the chaff, so that we remember the greatness of the wheat. Here's a simple platformer to pass some time: The Spyware Who Loved Me.

Chess with a bazooka

I must say, this Er Aran is one strange game. The art and music are wonderful. I think it's meant for two players. The introduction by the author is worth reading.

Son vs daughter riddle

Are you confident enough with your answer?

1. In a two-child family, one child is a boy. What is the probability that the other child is a girl?
2. In a two-child family, the elder child is a boy. What is the probability that the other child is a girl?

Special: All the best to the S&R Team for MH370, we're counting on you!

Determining if a line intersects a circle

Initiate Ivan has just been hired as an intern. He is tasked with solving a seemingly simple problem.

Egg-ish puzzles

I had eggs this morning, so I figured some easy puzzles on eggs would fit the occasion...

The careless mistakes that programmers make

This week has been a busy one, and I do wonder if my sexier-than-ever voice now is a sign that I should take a break. In any case, today I would like to share an "algorithm" I saw at the workplace. It is gentle reminder to always test your code...

Picking balls from bags (solution)

This is the solution to this puzzle: Picking balls from bags

Picking balls from bags

There are 3 bags on the table. The first bag contains a white ball and a black ball. The second bag contains two white balls. The third bag contains two black balls. They are all labelled on the outside accordingly.

Mr. Mallory comes and switches all the labels, so that they are all wrong.

You come along to the scene, aware of what Mr. Mallory did. Unfortunately, you do not know the original arrangement of the labels.

How many balls must you pick out from the bags before you can recover the original arrangement of the labels?