/**************************************************************

    Problem:

    User: BLADEVIL

    Language: Pascal

    Result: Accepted

    Time: ms

    Memory: kb

****************************************************************/

 

//By BLADEVIL

var

    n, m                        :longint;

    map                         :array[..,..] of longint;

    ans, len1, len, len2        :longint;

    left, right, down           :array[..,..] of longint;

     

function max(a,b:longint):longint;

begin

    if a>b then max:=a else max:=b;

end;

 

function min(a,b:longint):longint;

begin

    if a>b then min:=b else min:=a;

end;

     

procedure init;

var

    i, j, k                     :longint;

    ss                          :ansistring;

begin

    readln(n,m);

    for i:= to n do

    begin

        readln(ss);

        k:=;

        for j:= to length(ss) do

            if ss[j]<>' ' then

            begin

                inc(k);

                if ss[j]='F' then map[i,k]:= else map[i,k]:=;

            end;

    end;

     

    for i:= to n do

        for j:= to m do

            if map[i,j]= then left[i,j]:= else left[i,j]:=left[i,j-]+;

             

    for i:=n downto  do

        for j:=m downto  do

        begin

            if map[i,j]= then down[i,j]:= else down[i,j]:=down[i+,j]+;

            if map[i,j]= then right[i,j]:= else right[i,j]:=right[i,j+]+;

        end;

     

end;

 

procedure main;

var

    i, j, k                     :longint;

begin

    for i:= to n do

        for j:= to m do

            if map[i,j]= then

            begin

                len:=;

                len1:=maxlongint div ;

                len2:=maxlongint div ;

                for k:= to down[i+,j] do

                begin

                    len1:=min(len1,left[i+k,j]);

                    len2:=min(len2,right[i+k,j]);

                    ans:=max(ans,(len1+len2-)*k);

                end;

                if len1>=maxlongint div  then continue;

                inc(len,len1);

                ans:=max(ans,(len-)*down[i+,j]);

            end;

    writeln(ans*);

end;

 

begin

    init;

    main;

end.