5 6

R F F F F F

F F F F F F

R R R F F F

F F F F F F

F F F F F F

45

#include<bits/stdc++.h>

using namespace std;

//input by bxd

#define rep(i,a,b) for(int i=(a);i<=(b);i++)

#define repp(i,a,b) for(int i=(a);i>=(b);--i)

#define RI(n) scanf("%d",&(n))

#define RII(n,m) scanf("%d%d",&n,&m)

#define RIII(n,m,k) scanf("%d%d%d",&n,&m,&k)

#define RS(s) scanf("%s",s);

#define ll long long

#define REP(i,N)  for(int i=0;i<(N);i++)

#define CLR(A,v)  memset(A,v,sizeof A)

#define inf 0x3f3f3f3f

//////////////////////////////////

const int N=+;

int dp[N][N];

int mp[N][N];

int ri[N][N],le[N][N],up[N][N];

int main()

{

    char s;

    int n,m;

    RII(n,m);

    rep(i,,n)

    rep(j,,m)

    {

        cin>>s;

        if(s=='F')mp[i][j]=;

        else mp[i][j]=;

        ri[i][j]=le[i][j]=j;

        up[i][j]=;

    }

    rep(i,,n)

    rep(j,,m)

    if(mp[i][j]==mp[i][j-]&&mp[i][j]==)

    le[i][j]=le[i][j-];

    rep(i,,n)

    repp(j,m-,)

    if(mp[i][j]==mp[i][j+]&&mp[i][j]==)

    ri[i][j]=ri[i][j+];

    int ans=;

    rep(i,,n)

    rep(j,,m)

    if(mp[i][j])

    {

       if(i>)

           if(mp[i-][j])//如果状态需要转移的话

           {

            le[i][j]=max(le[i][j],le[i-][j]);

            ri[i][j]=min(ri[i][j],ri[i-][j]);

            up[i][j]=up[i-][j]+;

           }

        int d=ri[i][j]-le[i][j]+;

      //  if(d!=up[i][j])正方形也是矩形 所以不用加

        ans=max(ans,d*up[i][j]);

    }

    cout<<ans*;

    return ;

}