-----------------------My program-------------------------------------
const q = 40;
var
counter,check,l,i,j,n:integer;
s:string;
a:array [1..q,1..q] of integer;
ch:string;
begin
  readln (n);
  for i:=1 to n do
  begin
  for l:=1 to N DO
  begin
    readln (ch);
    if ch='.' then
      begin
         a[i,l]:=1
      end
      else a[i,l]:=-1;
  end;
  end;
  a[1,1]:=2;
  a[n,n]:=2;
  check:=1;
  while (check=1) do
  begin
    check:=0;
    for i:=1 to n do
    begin
      for j:=1 to n do
      begin
        if a[i,j]=2 then
        begin
          a[i,j]:=3;
          if a[i-1,j]=1 then a[i-1,j]:=2;
          if a[i,j-1]=1 then a[i,j-1]:=2;
          if a[i+1,j]=1 then a[i+1,j]:=2;
          if a[i,j+1]=1 then a[i,j+1]:=2;
          check:=1;
        end;
      end;
    end;
  end;
  for i:=1 to n do
  begin
    for j:=1 to n do
    begin
      if a[i,j]=3 then
      begin
        if (a[i-1,j]<>3) then inc (counter);
        if (a[i+1,j]<>3) then inc (counter);
        if (a[i,j+1]<>3) then inc (counter);
        if (a[i,j-1]<>3) then inc (counter);
      end;
    end;
  end;
  counter:=counter-4;
  writeln (counter*9);
end.
{Where is my error? I have WA}

3
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Correct answer is 72