Monday, 18 January 2016

strategy - Rearranging Frogs



This is a small puzzle that I saw a lot as a kid but surprisingly haven't found on this site. Enjoy!




You have six frogs arranged on seven lily pads in a line: three male frogs facing right on the leftmost lily pads and three female frogs facing left on the rightmost lily pads.




M M M _ F F F



How can you switch the positions of the frogs (have the male frogs end up where the female frogs currently sit and vice versa)?


Rules:



  • Each lily pad can hold only one frog.

  • Frogs can only move in the direction they are facing.

  • Frogs can move forward to an empty lily pad or jump over one frog to the empty lily pad on the other side.




Answer



Basic idea:



They need to try to mix perfectly - MFMFMF



Process:



MMM_FFF
MM_MFFF
MMFM_FF

MMFMF_F
MMF_FMF
M_FMFMF
_MFMFMF
FM_MFMF
FMFM_MF
FMFMFM_
FMFMF_M
FMF_FMM
F_FMFMM

FF_MFMM
FFFM_MM
FFF_MMM



Also, I'm also surprised this isn't on the site already in a different form. It's quite possible that I just didn't search for the right terms.


No comments:

Post a Comment

Understanding Stagnation point in pitot fluid

What is stagnation point in fluid mechanics. At the open end of the pitot tube the velocity of the fluid becomes zero.But that should result...