(;GM[1]FF[4]SZ[19]
GN[Problem 2]
PC[http://senseis.xmp.net/?DoubleSnapback]AP[GoWiki:2009]
DT[2011-11-30]
C[Diagram from http://senseis.xmp.net/?DoubleSnapback

Problem 2]
PL[B]

AB[ap][bp][cp][dp][ep][fp][gp][cq][gq][er][gr][gs]
AW[aq][bq][dq][eq][fq][ar][cr][fr][as][es][fs]


;
)
