(;
GM[1]
SZ[19]
AW[dd][dc][df][ch][bg][co][dp][gq][jq][rp][rn][sn][sm][qm][ql][rl][qk][qj][pj][qi][ri][qh][qd][rd]
AW[qa][pa][pb][pc][oc][od][oe][mb][mc][lc][kc][kd][kb][jb][hb][hj][nk][gk][hk][cr][dq][hp]
AW[ho][cn][dm][cl][dl]
AB[bh][cj][cm][oq][qp][qn][qo][ro][so][rh][sg][rf][re][qe][pe][pd][qc][rc][qb][ra][ne][nf]
AB[md][ld][nb][ib][ic][jc][jd][je][ke][fc][fe][gi][pk][ok][oj][ol][pi][ph][gj][dr][eq][fp]
AB[gp][fn][dn][hm][em][jm][fk]
LB[jm:A]
C[Supplement to Problem 123. ]
)
)