i:0:"i/12"
m:i|"az""SE"?i
f:{(s;m):x;s&:(1|999*~2>-':m)*999,-1_1+s;+'|'(s;m)}
(*(4 f/)/(999*~"S"=i;m)).*'&"E"=i
&/(*(4 f/)/(999*~"E"=i;-m))./:+&"a"=i