Problem 3916 was originally like this but was changed after doubts about the A and B exchange. To the rescue!
Author BartTM Created 2004-02-13
Difficulty 8 dan (history) Source Variation on problem 3916 by ciith
AVG solve time 61 sec Stars 2.5  (4 votes)
User attempts 404 / 3281 Collections N/A
Genre life and death Your attempts N/A
Similar problems
Created 2004-02-13
Source Variation on problem 3916 by ciith
Stars 2.5  (4 votes)
Collections N/A
Your attempts N/A