This is GNU Go, a Go program. Contact gnugo@gnu.org, or see
http://www.gnu.org/software/gnugo/ for more information.

Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
2008 and 2009 by the Free Software Foundation.

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation - version 3 or
at your option any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License in file COPYING for more details.

You should have received a copy of the GNU General Public
License along with this program; if not, write to the Free
Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02111, USA.

(;GM[1]FF[3]
SZ[19];B[oe]
(;W[qc]N[San-san invasion]
(;B[oc]MA[kg]
(;W[qe]MA[mg];B[pg]MA[ki];W[qg];B[ph]MA[li])

(;W[qf]MA[mi];B[qb]
C[S
# According to KJD, Q13 is an option too.  But I think Q13 is generally
 too cosmic for GNU Go.  /pp]
MA[mg];W[rb]C[U]MA[ng];B[qd]MA[ng];W[pc]C[U]MA[ng];B[pd]C[U]MA[nf];
W[rd]C[U]MA[nf];B[pb]MA[nf];W[rc]MA[ng];B[pg]MA[lh])
)

(;B[pc]C[# Looks risky for GNU Go.  /pp];W[pb]MA[mf];B[qd]
C[U
# Is it urgent enough?  /pp]MA[mf];W[oc]C[U]MA[mf];B[pd]C[U]MA[mf]
;W[rb]C[U]MA[nf];B[rc]MA[mg];W[qb]C[U]MA[nf];B[nc]MA[lf])
)

(;W[pd]N[Hoshi invasion];B[pe]MA[nh]
(;W[qd]MA[lg];B[qe]MA[mg]
(;W[od]MA[mf];B[nd]MA[kf];W[nc]MA[mf];B[mc]MA[kf];W[nb]MA[lf];B[mb]
MA[lf];W[pb]MA[lf];B[md]MA[lf])

(;W[nc]MA[lf];B[oc]MA[lf];W[od]MA[mf];B[nd]MA[lf]
(;W[ob]MA[mf];B[mc]MA[lf];W[nb]C[U]MA[lf];B[md]MA[lf])

(;W[md]C[# This empasizes the top, hence larger area.  /pp]MA[jf];
B[ne]MA[lg];W[mc]MA[kf];B[rd]MA[lg];W[pb]MA[me];B[qb]C[# Tesuji.]
MA[me];W[pc]MA[me];B[qc]MA[me];W[ob]MA[me])
)
)

(;W[qe]C[# Looks risky for GNU Go.  /pp];B[qf]MA[nh];W[qd]MA[ng];B[od]
MA[ng];W[rf]MA[nh];B[qg]MA[ni];W[rg]MA[ni];B[qh]MA[mj];W[ob]
C[j
# I think so.  /pp]MA[mh];B[oc]MA[lh];W[pb]MA[me];B[mc]C[j]MA[kh])

(;W[oc]MA[kf]
(;B[qe]MA[mh];W[mc]MA[kf];B[qc]MA[lf];W[jc]MA[ie])

(;B[qd]MA[mh];W[qc]MA[mf];B[qe]C[U]MA[nf];W[rc]MA[nf];B[nc]MA[mf];
W[nb]MA[me];B[od]MA[me];W[pc]C[U]MA[me];B[mc]MA[lf];W[mb]MA[ke];B[lc]
MA[kg])
)
)

(;W[qd]N[Komoku invasion]
(;B[qe]
C[# According to KJD, this emphasizes top despite the way it 
looks.  /pp]
MA[lg];W[re]MA[mg]
(;B[pe]C[U
# I think so.  /pp]MA[nf]
(;W[rf]C[U]MA[ng];B[oc]MA[lf];W[pc]MA[nf];B[ob]MA[nf])

(;W[qf]C[0
# Bad.]MA[oh]
(;B[rf]MA[oh];W[rg];B[rd];W[sf];B[qc])

(;B[rd]C[0
# Bad too.]MA[oh];W[rc]MA[ng];B[rf];W[sd];B[qg];W[oc])
)
)

(;B[rf]C[0
# Mistake.];W[pe];B[qf];W[pd];B[pf];W[od])
)

(;B[pc]MA[lf];W[qc]MA[nf];B[pf]MA[mg]
(;W[pd]MA[mg];B[od]C[U]MA[ng]
(;W[oc]MA[mf];B[nc]C[U]MA[mf];W[pb]MA[mf];B[ob]MA[mf];W[rf]MA[mg])

(;W[ob]
C[:-,shape(1)
# A trick to avoid ko.  I think it's better for GNU Go.  /pp]
MA[mf];B[oc]MA[mf];W[pb]MA[nf];B[nb]MA[mf];W[rf]MA[mg];B[mc];W[qg])
)

(;W[rf]MA[nh];B[pb]MA[lg];W[qg]MA[ni];B[kc]MA[jh])
)
)

)