1 #include <bits/stdc++.h> 2 #define _for(i,a,b) for(int i = (a);i < b;i ++) 3 #define _rep(i,a,b) for(int i = (a);i > b;i --) 4 #define INF 0x3f3f3f3f 5 #define MOD 1000000007 6 typedef long long ll; 7 using namespace std; 8 inline ll read() 9 { 10 ll ans = 0; 11 char ch = getchar(), last = ' '; 12 while(!isdigit(ch)) last = ch, ch = getchar(); 13 while(isdigit(ch)) ans = (ans << 1) + (ans << 3) + ch - '0', ch = getchar(); 14 if(last == '-') ans = -ans; 15 return ans; 16 } 17 inline void write(ll x) 18 { 19 if(x < 0) x = -x, putchar('-'); 20 if(x >= 10) write(x / 10); 21 putchar(x % 10 + '0'); 22 } 23 24 int N,M; 25 int a[1003][1003]; 26 int lef[1003][1003]; 27 int ri[1003][1003]; 28 int up[1003][1003]; 29 int main() 30 { 31 N = read(),M = read(); 32 _for(i,1,N+1) 33 _for(j,1,M+1) 34 { 35 char c; 36 cin >> c; 37 if(c=='R') 38 a[i][j] = 1; 39 else 40 a[i][j] = 0; 41 } 42 43 _for(j,1,M+1) 44 { 45 if(!a[1][j]) 46 up[1][j] = 1; 47 _for(i,2,N+1) 48 if(!a[i][j]) 49 up[i][j] = up[i-1][j]+1; 50 } 51 52 _for(i,1,N+1) 53 { 54 if(!a[i][1]) 55 lef[i][1] = 1; 56 _for(j,2,M+1) 57 if(!a[i][j]) 58 lef[i][j] = lef[i][j-1]+1; 59 } 60 61 _for(i,1,N+1) 62 { 63 if(!a[i][M]) 64 ri[i][M] = 1; 65 _rep(j,M-1,0) 66 if(!a[i][j]) 67 ri[i][j] = ri[i][j+1]+1; 68 } 69 int ans = 0; 70 _for(i,1,N+1) 71 _for(j,1,M+1) 72 { 73 if(i>1 && !a[i][j] && !a[i-1][j]) 74 { 75 lef[i][j] = min(lef[i-1][j],lef[i][j]); 76 ri[i][j] = min(ri[i-1][j],ri[i][j]); 77 } 78 ans = max(ans,up[i][j]*(ri[i][j]+lef[i][j]-1)); 79 } 80 write(3*ans); 81 return 0; 82 }