This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
/*
	dp[i][j] = potential value in range (i, j) -> (N, M);
	dp[i][j] = dp[i+1][j] + dp[i][j+1] - dp[i+1][j+1] + (sum())
*/
const int mxN = 2e3+10;
ll N, M;
char land[mxN][mxN]; 
ll cum[mxN][mxN];
ll maxLen(int i, int ii, int j) {
	int l = j, r = M, mid;
	while(l < r) {
		mid = (l + r + 1) >> 1;
		if ((cum[ii][mid] + cum[i-1][j-1] - cum[ii][j-1] - cum[i-1][mid]) == 0) l = mid;
		else r = mid - 1;
	}
	return l - j + 1;
}
ll calc(int i, int j) {
	ll ret = 0;
	if (land[i][j] == '#')
		return ret;
	for (ll ii = i; ii <= N && land[ii][j] != '#'; ii++) {
		ll len = maxLen(i, ii, j);
		ret += (len*(len+1)/2) * (ii-i+1);
	}
	return ret;
}
void solve() {
	cin >> N >> M;
	for (int i = 1; i <= N; i++) {
		for (int j = 1; j <= M; j++) {
			cin >> land[i][j];
			cum[i][j] = ((land[i][j] == '#') + cum[i-1][j] + cum[i][j-1] - cum[i-1][j-1]);
		}
	}
	
	vector<vector<ll>> dp(mxN, vector<ll>(mxN, 0));
	dp[N][M] = (land[N][M] != '#');
	for (int i = N; i; i--) {
		for (int j = M; j; j--) {
			dp[i][j] = dp[i+1][j] + dp[i][j+1] - dp[i+1][j+1] + calc(i, j);
		}
	}
	// for (int i = 1; i <= N; i++) {
	// 	for (int j = 1; j <= M; j++) {
	// 		cout << dp[i][j] << " \n"[j == M];
	// 	}
	// }
	cout << dp[1][1];
}
int main() {
	
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	solve();
}
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