#include using namespace std; typedef long long ll; template using Graph = vector>; #define REP(i, a, b) for (int i = (int)(a); i < (int)(b); i++) #define rep(i, a) REP(i, 0, a) #define EACH(i, a) for (auto i: a) #define ITR(x, a) for (__typeof(a.begin()) x = a.begin(); x != a.end(); x++) #define ALL(a) (a.begin()), (a.end()) #define HAS(a, x) (a.find(x) != a.end()) #define endl '\n' int dx4[] = {1, 0, -1, 0}, dy4[] = {0, 1, 0, -1}; int dx8[] = {1, 1, 0, -1, -1, -1, 0, 1}, dy8[] = {0, 1, 1, 1, 0, -1, -1, -1}; int N, M; char G[1005][1005]; int depth[1005][1005]; int ans[2]; bool is_inside(int x, int y) { return (0 <= x && x < M && 0 <= y && y < N); } int dfs(int x, int y) { G[y][x] = 'X'; int res = 1; rep(i, 8) { int nx = x + dx8[i], ny = y + dy8[i]; if (!is_inside(nx, ny)) continue; if (G[ny][nx] != 'x') continue; res = dfs(nx, ny) + 1; } return res; } void dfs_dot(int x, int y, int d) { depth[y][x] = d; rep(i, 4) { int nx = x + dx4[i], ny = y + dy4[i]; if (!is_inside(nx, ny)) continue; if (G[ny][nx] != '.') continue; if (depth[ny][nx] != -1) continue; dfs_dot(nx, ny, d); } } int main(void) { cin.tie(0); ios::sync_with_stdio(false); cin >> N >> M; rep(y, N + 2) rep(x, M + 2) G[y][x] = '.'; rep(y, N) rep(x, M) cin >> G[y + 1][x + 1]; rep(y, N + 2) rep(x, M + 2) depth[y][x] = -1; N += 2; M += 2; int d = -1; rep(y, N) rep(x, M) { if (G[y][x] == 'x') { ans[d%2] += dfs(x, y); } if (G[y][x] == '.') { if (depth[y][x] == -1) dfs_dot(x, y, d + 1); d = depth[y][x]; } } cout << max(ans[0], ans[1]) << endl; return 0; }