#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <stdlib.h>
#include <vector>
using namespace std;
int N, M;
char G[3001][3001];
vector<int> D[3001][3001];
long long S;
int main(){
scanf("%d %d", &N, &M);
for (int i = 1; i <= N; i++)
for (int j = 1; j <= M; j++)
scanf(" %c", &G[i][j]);
for (int j = 1; j <= M; j++){
for (int i = 1; i <= N; i++){
if (G[i][j] == 'R'){
int s = D[i - 1][j].size();
for (int k = j; G[i][k] == 'R'; k--){
int d = (j - k < s ? D[i - 1][j][j - k] : 0);
D[i][j].push_back(d + 1);
S += d + 1;
}
}
D[i - 1][j].clear();
}
}
printf("%lld", S);
return 0;
}
