• 0
Sign in to follow this  
Followers 0

Stampless Foreheads

Question

Posted · Report post

Feeling left out, as everyone else around here seems to be running around with various polychromatic items attached to their foreheads, you and I decided to play a friendly variant of Indian Poker. Because I'm partial to pointy things that resemble weapons, I take all the spades (13 cards) from a standard 52 card deck, shuffle them, and deal us each one. We each then affix the card to our distinctly-bare-up-until-now foreheads without looking at our own cards. Then we take turns declaring "higher" (if we think our card is higher than the other's), "lower" (if we think our card is lower than the other's), or we say "pass" (if we don't know). Since you and I both hate to be wrong, neither will declare unless we have a logical reason to do so.

What is the maximum number of iterations it will take before one us can declare?

0

Share this post


Link to post
Share on other sites

4 answers to this question

  • 0

Posted · Report post

A: "Pass" unless B has 2 or A

B: "Pass" unless A has 2,3,K or A

A: "Pass" unless B has 3,4,Q or K

B: "Pass" unless A has 4,5,J or Q

A: "Pass" unless B has 5,6,10 or J

B: "Pass" only if A has 8

At this point A will declare as he knows he has an 8. B should have 7 or 9 for this to continue for so long.

0

Share this post


Link to post
Share on other sites
  • 0

Posted · Report post

A logical reason for the first declare is the other's card is above or below the average value for a suit: the seven of spades. If it is the seven we say idk. Based on that response and what the opponent sees, s/he replies with similar logic and eventually the process converges.

I'm gonna make a wild guess before going through the analysis and say seven iterations.

But halving the intervals each time might make it four. Idk.
0

Share this post


Link to post
Share on other sites
  • 0

Posted · Report post

Nice puzzle, nice solve!

0

Share this post


Link to post
Share on other sites
  • 0

Posted · Report post

Yep, just a simple little puzzle that I thought of on my way to something massively more complicated...

Indian Head Go Fish ;P

0

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now
Sign in to follow this  
Followers 0

  • Recently Browsing   0 members

    No registered users viewing this page.