#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; #define is_mul_overflow(a, b) \ ((b != 0) && (a > LLONG_MAX / b || a < LLONG_MIN / b)) typedef pair pli; typedef pair pil; typedef pair pll; typedef pair pii; typedef pair pdd; typedef pair piii; typedef pair pil; typedef pair plii; typedef pair pdi; typedef long long ll; typedef unsigned long long ull; typedef pair puu; typedef long double ld; const int N = 2000086, MOD = 998244353, INF = 0x3f3f3f3f, MID = 333; const long double EPS = 1e-8; int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1}; // int dx[8] = {1, 1, 0, -1, -1, -1, 0, 1}, dy[8] = {0, 1, 1, 1, 0, -1, -1, -1}; // int dx[8] = {2, 1, -1, -2, -2, -1, 1, 2}, dy[8] = {1, 2, 2, 1, -1, -2, -2, -1}; int n, m, cnt; int w[N]; vector num; ll res; ll lowbit(ll x) { return x & -x; } ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; } ll lcm(ll a, ll b) { return a / gcd(a, b) * b; } inline double rand(double l, double r) { return (double)rand() / RAND_MAX * (r - l) + l; } inline ll qmi(ll a, ll b, ll c) { ll res = 1; while (b) { if (b & 1) res = res * a % c; a = a * a % c; b >>= 1; } return res; } inline ll qmi(ll a, ll b) { ll res = 1; while (b) { if (b & 1) res *= a; a *= a; b >>= 1; } return res; } inline double qmi(double a, ll b) { double res = 1; while (b) { if (b & 1) res *= a; a *= a; b >>= 1; } return res; } // inline ll C(ll a, ll b) { if (a < b) return 0; if (b > a - b) b = a - b; ll res = 1; for (ll i = 1, j = a; i <= b; i++, j--) { res = res * (j % MOD) % MOD; res = res * qmi(i, MOD - 2, MOD) % MOD; } return res; } inline ll C(ll a, ll b, int* c) { if (a < b) return 0; ll res = 1; for (ll j = a, i = 1; i < b + 1; i++, j--) res *= j; for (ll j = a, i = 1; i < b + 1; i++, j--) res /= i; return res; } inline int find_(int x) { return lower_bound(num.begin(), num.end(), x) - num.begin(); } bool st[1089][1089]; char s[1089][1089]; void dfs(int x, int y) { res++; st[x][y] = 1; for (int i = 0; i < 4; i++) { int a = x + dx[i], b = y + dy[i]; if (a < 1 || a > n || b < 1 || b > m || st[a][b] || s[a][b] != s[x][y]) continue; dfs(a, b); } } void dfs2(int x, int y) { char p = s[x][y]; s[x][y] = '.'; for (int i = 0; i < 4; i++) { int a = x + dx[i], b = y + dy[i]; if (a < 1 || a > n || b < 1 || b > m || s[a][b] != p) continue; dfs2(a, b); } } int main() { cin >> n >> m; for (int i = 1; i < n + 1; i++) scanf("%s", s[i] + 1); for (int i = 1; i < n + 1; i++) for (int j = 1; j < m + 1; j++) if (s[i][j] != '.' && !st[i][j]) { res = 0; dfs(i, j); if (res >= 4) dfs2(i, j); } for (int i = 1; i < n + 1; i++) printf("%s\n", s[i] + 1); }