3 ms·

Also very challenging for chess players is retrograde analysis, where you have to find the only possible legal moves to reach the given position. See the cover

Also very challenging for chess players is retrograde analysis, where you have to find the only possible legal moves to reach the given position. See the cover of this book by Smullyan http://ecx.images-amazon.com/images/I/81y-bMMYCoL.jpg http://ecx.images-amazon.com/images/I/81y-bMMYCoL.jpg

sanderjd 11y ago
Thanks for that link, it was fun and took me quite awhile to figure out!
- philh 11y ago
  Vs gur obneq vf hcfvqr-qbja, juvgr cebzbgrq gb n ovfubc naq gura oynpx zbirq bhg bs purpx. Bgurejvfr V pna'g guvax bs nalguvat. Vf gung jung lbh pnzr hc jvgu?
  - Relaxx 11y ago
    V guvax juvgr unq n xavtug ba o6, zbirq vg gb n8 naq gura gur oynpx xvat pncgherq vg.