var n,m,i,j:integer;
a,b:array[0..1001,0..1001] of integer;
min,f,si,sj,fi,fj,k:longint;






begin


assign(input,'input.txt');
reset(input);
assign(output,'output.txt');
rewrite(output);
read(n,m);
for i:=1 to n do
for j:=1 to m do
read(a[i,j]);
for i:=1 to n do
for j:=1 to m do
b[i,j]:=a[i,j];


for i:=1 to n do begin a[i,0]:=0;a[i,m+1]:=0;end;
for i:=1 to m do begin a[0,j]:=0;a[n+1,j]:=0;end;
k:=4;
f:=1;
while (f=1) do begin
f:=0;
for i:=1 to n do
for j:=1 to m do  begin
if (a[i,j]=k) and (a[i-1,j]=1) then begin f:=1; a[i-1,j]:=k+1;end;
if (a[i,j]=k) and (a[i+1,j]=1) then begin f:=1;a[i+1,j]:=k+1;end;
if (a[i,j]=k) and (a[i,j-1]=1) then begin f:=1;a[i,j-1]:=k+1;end;
if (a[i,j]=k) and (a[i,j+1]=1) then begin f:=1;a[i,j+1]:=k+1;end;


end;
k:=k+1;
end;
for i:=1 to n do
for j:=1 to m do begin
if a[i,j]=4 then begin si:=i;sj:=j;end;
if a[i,j]=3 then begin fi:=i;fj:=j;end;
end;
min:=maxint;
if (a[fi-1,fj]>2) and (a[fi-1,fj]<min) then min:=a[fi-1,fj];
if (a[fi+1,fj]>2) and (a[fi+1,fj]<min) then min:=a[fi+1,fj];
if (a[fi,fj-1]>2) and (a[fi,fj-1]<min) then min:=a[fi,fj-1];
if (a[fi,fj+1]>2) and (a[fi,fj+1]<min) then min:=a[fi,fj+1];
if min<maxint then writeln(min-3)
else
begin
for i:=1 to n do
for j:=1 to m do
a[i,j]:=b[i,j];


for i:=1 to n do begin a[i,0]:=0;a[i,m+1]:=0;end;
for i:=1 to m do begin a[0,j]:=0;a[n+1,j]:=0;end;
k:=4;
f:=1;
while (f=1) do begin
f:=0;
for i:=1 to n do
for j:=1 to m do  begin
if (a[i,j]=k) and ((a[i-1,j]=1)or (a[i-1,j]=2)) then begin f:=1; a[i-1,j]:=k+1;end;
if (a[i,j]=k) and ((a[i+1,j]=1)or(a[i+1,j]=2)) then begin f:=1;a[i+1,j]:=k+1;end;
if (a[i,j]=k) and ((a[i,j-1]=1)or(a[i,j-1]=2)) then begin f:=1;a[i,j-1]:=k+1;end;
if (a[i,j]=k) and ((a[i,j+1]=1)or(a[i,j+1]=2)) then begin f:=1;a[i,j+1]:=k+1;end;


end;
k:=k+1;
end;
for i:=1 to n do
for j:=1 to m do begin
if a[i,j]=4 then begin si:=i;sj:=j;end;
if a[i,j]=3 then begin fi:=i;fj:=j;end;
end;
min:=maxint;
if (a[fi-1,fj]>2) and (a[fi-1,fj]<min) then min:=a[fi-1,fj];
if (a[fi+1,fj]>2) and (a[fi+1,fj]<min) then min:=a[fi+1,fj];
if (a[fi,fj-1]>2) and (a[fi,fj-1]<min) then min:=a[fi,fj-1];
if (a[fi,fj+1]>2) and (a[fi,fj+1]<min) then min:=a[fi,fj+1];






if min=maxint then writeln('NO EXIT') else writeln(min-3);
end;
close(output);
close(input);

end.