toplevel "T";
"T" and "A" "B" "C";
"A" or "D" "E";
"B" or "F" "G";
"C" or "H" "I";
"D" or "K" "M";
"F" or "N" "O";
"H" or "P" "Q";
"E" lambda=9 dorm=1;
"G" lambda=1 dorm=1;
"I" lambda=7 dorm=1;
"K" lambda=4 dorm=1;
"M" lambda=5 dorm=1;
"N" lambda=3 dorm=1;
"O" lambda=8 dorm=1;
"P" lambda=6 dorm=1;
"Q" lambda=2 dorm=1;