deep给的这个:=LET(a,A1:D4,b,D1,c,A4,d,{"C1","D2"},e,{"→","←","↑","↓"},f,LAMBDA(g,h,i,j,IF(h=c,IF(COUNTA(j)=ROWS(a)*COLUMNS(a),TEXTJOIN("→",1,i),"无解"),LET(k,COLUMN(INDIRECT(h)),l,ROW(INDIRECT(h)),m,{1,0;-1,0;0,-1;0,1},n,MAP(m,LAMBDA(o,OFFSET(INDIRECT(h),INDEX(o,2),INDEX(o,1)))),p,FILTER(n,(ISNUMBER(MATCH(n,a,0)))*(COUNTIF(j,n)=0),""),q,IF(ROWS(j)=1,IF(COUNTIF(d,p),p,""),p),r,IF(q="","无解",REDUCE("",q,LAMBDA(s,t,IF(s="无解",g(g,ADDRESS(ROW(t),COLUMN(t),4),VSTACK(i,ADDRESS(ROW(t),COLUMN(t),4)),VSTACK(j,t)),s)))),IF(r="","无解",r)))),result,f(f,b,"D1","D1"),IF(result="无解","无解",TEXTJOIN("→",1,result)))