Problem	359
Created	2001-01-22
Name	Carpenter's square
Source	life & death
Rating

Difficulty	7 dan
Average Solve Time	44 secs
User Attempts	652 / 4213
Solve Ratio Rating	1 dan
	rating history

If you fully understand the carpenter's square you are a strong dan-player! (This is one sub-problem to the carpenter's square)

(;AW[pb]AW[qb]AW[oc]AW[pc]AW[pd]AW[qd]AW[rd]AW[qe]AB[nb]AB[ob]AB[rb]AB[nc]AB[nd]AB[od]AB[pe]AB[re]AB[pf]AB[qf]AB[rf]C[Black to kill the corner.]SZ[19]GM[1]FF[3]RU[Japanese]HA[0]KM[5.5]PW[White]PB[Black]GN[White (W) vs. Black (B)]DT[2001-01-22]SY[Cgoban 1.9.11]TM[-] (;B[rc];W[sd] (;B[pa];W[ra] (;B[sc];W[sb];B[sa]C[ko]) (;B[sb];W[sc]C[seki];B[oa];W[qa]C[seki])) (;B[ra];W[sb] (;B[sc];W[qa];B[se];W[qc];B[pa]C[RIGHT]) (;B[pa];W[qa] (;B[sc];W[oa];B[se];W[qc];B[pa]C[RIGHT]) (;B[se];W[sc]C[seki]) (;B[oa];W[sc]C[seki]))) (;B[qa];W[pa] (;B[ra];W[sb] (;B[sc];W[qc]) (;B[se];W[sc]C[seki])) (;B[sb];W[ra]C[alive])) (;B[sc];W[ra] (;B[pa];W[sb]C[ko];B[sa]C[ko]) (;B[sb];W[pa]))) (;B[sc];W[sd] (;B[ra];W[rc];B[pa];W[qa];B[se];W[sb]) (;B[rc];W[ra];B[pa];W[sb]C[ko];B[sa]C[ko]) (;B[pa];W[ra];B[rc];W[sb]C[ko];B[sa]C[ko])) (;B[sb];W[rc] (;B[ra];W[sc];B[pa];W[qa];B[se];W[sa]) (;B[sd];W[sc];B[pa];W[qa])) (;B[ra];W[rc];B[pa];W[qa];B[sd];W[sc]) (;B[pa];W[ra];B[rc];W[sc];B[sb];W[sd];B[oa];W[qa]C[seki]) (;B[sd];W[sc] (;B[se];W[rc]) (;B[rc];W[se] (;B[sb];W[ra] (;B[pa];W[sd]C[seki]) (;B[sd]C[ko])) (;B[ra];W[sb] (;B[pa];W[qa]C[seki]) (;B[sa];W[sd];B[pa];W[qa]C[alive]))) (;B[sb];W[rc];B[pa];W[qa]) (;B[pa];W[ra] (;B[rc];W[se];B[sb];W[sd]C[seki]) (;B[sb];W[rc]))))