// -*- coding:utf-8-unix -*- // #![feature(map_first_last)] #![allow(dead_code)] #![allow(unused_imports)] #![allow(unused_macros)] // use core::num; use std::cmp::*; use std::fmt::*; use std::hash::*; use std::io::BufRead; use std::iter::FromIterator; use std::*; use std::{cmp, collections, fmt, io, iter, ops, str}; const INF: i64 = 1223372036854775807; const UINF: usize = INF as usize; const LINF: i64 = 2147483647; const INF128: i128 = 1223372036854775807000000000000; const MOD1: i64 = 1000000007; const MOD9: i64 = 998244353; const MOD: i64 = MOD9; // const MOD: i64 = MOD2; const UMOD: usize = MOD as usize; const M_PI: f64 = 3.14159265358979323846; // use proconio::input; // const MOD: i64 = INF; use cmp::Ordering::*; use std::collections::*; use std::io::stdin; use std::io::stdout; use std::io::Write; macro_rules! p { ($x:expr) => { //if expr println!("{}", $x); }; } macro_rules! vp { // vector print separate with space ($x:expr) => { println!( "{}", $x.iter() .map(|x| x.to_string()) .collect::>() .join(" ") ); }; } macro_rules! d { ($x:expr) => { eprintln!("{:?}", $x); }; } macro_rules! yn { ($val:expr) => { if $val { println!("Yes"); } else { println!("No"); } }; } macro_rules! map{ // declear btreemap ($($key:expr => $val:expr),*) => { { let mut map = ::std::collections::BTreeMap::new(); $( map.insert($key, $val); )* map } }; } macro_rules! set{ // declear btreemap ($($key:expr),*) => { { let mut set = ::std::collections::BTreeSet::new(); $( set.insert($key); )* set } }; } //input output #[allow(dead_code)] fn read() -> T { let mut s = String::new(); std::io::stdin().read_line(&mut s).ok(); s.trim().parse().ok().unwrap() } #[allow(dead_code)] fn read_vec() -> Vec { read::() .split_whitespace() .map(|e| e.parse().ok().unwrap()) .collect() } #[allow(dead_code)] fn read_mat(n: u32) -> Vec> { (0..n).map(|_| read_vec()).collect() } #[allow(dead_code)] fn readii() -> (i64, i64) { let mut vec: Vec = read_vec(); (vec[0], vec[1]) } #[allow(dead_code)] fn readiii() -> (i64, i64, i64) { let mut vec: Vec = read_vec(); (vec[0], vec[1], vec[2]) } #[allow(dead_code)] fn readuu() -> (usize, usize) { let mut vec: Vec = read_vec(); (vec[0], vec[1]) } #[allow(dead_code)] fn readff() -> (f64, f64) { let mut vec: Vec = read_vec(); (vec[0], vec[1]) } fn readcc() -> (char, char) { let mut vec: Vec = read_vec(); (vec[0], vec[1]) } fn readuuu() -> (usize, usize, usize) { let mut vec: Vec = read_vec(); (vec[0], vec[1], vec[2]) } #[allow(dead_code)] fn readiiii() -> (i64, i64, i64, i64) { let mut vec: Vec = read_vec(); (vec[0], vec[1], vec[2], vec[3]) } #[allow(dead_code)] fn readuuuu() -> (usize, usize, usize, usize) { let mut vec: Vec = read_vec(); (vec[0], vec[1], vec[2], vec[3]) } pub struct Dsu { n: usize, // root node: -1 * component size // otherwise: parent parent_or_size: Vec, } impl Dsu { // 0 <= size <= 10^8 is constrained. pub fn new(size: usize) -> Self { Self { n: size, parent_or_size: vec![-1; size], } } pub fn merge(&mut self, a: usize, b: usize) -> usize { assert!(a < self.n); assert!(b < self.n); let (mut x, mut y) = (self.leader(a), self.leader(b)); if x == y { return x; } if -self.parent_or_size[x] < -self.parent_or_size[y] { std::mem::swap(&mut x, &mut y); } self.parent_or_size[x] += self.parent_or_size[y]; self.parent_or_size[y] = x as i32; x } pub fn same(&mut self, a: usize, b: usize) -> bool { assert!(a < self.n); assert!(b < self.n); self.leader(a) == self.leader(b) } pub fn leader(&mut self, a: usize) -> usize { assert!(a < self.n); if self.parent_or_size[a] < 0 { return a; } self.parent_or_size[a] = self.leader(self.parent_or_size[a] as usize) as i32; self.parent_or_size[a] as usize } pub fn size(&mut self, a: usize) -> usize { assert!(a < self.n); let x = self.leader(a); -self.parent_or_size[x] as usize } pub fn groups(&mut self) -> Vec> { let mut leader_buf = vec![0; self.n]; let mut group_size = vec![0; self.n]; for i in 0..self.n { leader_buf[i] = self.leader(i); group_size[leader_buf[i]] += 1; } let mut result = vec![Vec::new(); self.n]; for i in 0..self.n { result[i].reserve(group_size[i]); } for i in 0..self.n { result[leader_buf[i]].push(i); } result .into_iter() .filter(|x| !x.is_empty()) .collect::>>() } } fn main() { let (h, w) = readuu(); let mut vv: Vec> = vec![vec!['0' as char; (0) as usize]; (h) as usize]; for i in 0..h { let s: String = read(); let vvv = s.chars().collect(); vv[i] = vvv; } let mut dsu = Dsu::new(h * w); for i in 0..h { for j in 0..w { if i > 0 && vv[i][j] == vv[i - 1][j] { dsu.merge(i * w + j, (i - 1) * w + j); } if j > 0 && vv[i][j] == vv[i][j - 1] { dsu.merge(i * w + j, i * w + j - 1); } } } for i in 0..h { for j in 0..w { if dsu.size(i * w + j) >= 4 { vv[i][j] = '.'; } } } for i in 0..h { for j in 0..w { print!("{}", vv[i][j]); } println!(); } return; }