import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileWriter; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintWriter; import java.util.Comparator; import java.util.HashSet; import java.util.TreeSet; public class Main { public static void main(String[] args) throws NumberFormatException, IOException { ContestScanner in = new ContestScanner(); int h = in.nextInt(); int w = in.nextInt(); char[][] s = new char[h][w]; for(int i=0; i= h || j+l >= w || s[k+i][l+j]=='.' || copy[k][l] != 1) continue; copy[k][l] = 3; copy[k+i][l+j] = 2; } } boolean isok = true; notok:for(int k=0; k= h || l+w >= w || copy[k+i][l+j] !=2){ isok = false; break notok; } }else if(copy[k][l] == 1){ isok = false; break notok; } } } if(isok){ System.out.println("YES"); return; } } } System.out.println("NO"); return; } } class Node{ int id; HashSet edge = new HashSet(); public Node(int id) { this.id = id; } public void createEdge(Node node) { edge.add(node); } } class MyComp implements Comparator { final int idx; public MyComp(int idx){ this.idx = idx; } public int compare(int[] a, int[] b) { return a[idx] - b[idx]; } } class Reverse implements Comparator { public int compare(Integer arg0, Integer arg1) { return arg1 - arg0; } } class ContestWriter { private PrintWriter out; public ContestWriter(String filename) throws IOException { out = new PrintWriter(new BufferedWriter(new FileWriter(filename))); } public ContestWriter() throws IOException { out = new PrintWriter(System.out); } public void println(String str) { out.println(str); } public void print(String str) { out.print(str); } public void close() { out.close(); } } class ContestScanner { private BufferedReader reader; private String[] line; private int idx; public ContestScanner() throws FileNotFoundException { reader = new BufferedReader(new InputStreamReader(System.in)); } public ContestScanner(String filename) throws FileNotFoundException { reader = new BufferedReader(new InputStreamReader(new FileInputStream( filename))); } public String nextToken() throws IOException { if (line == null || line.length <= idx) { line = reader.readLine().trim().split(" "); idx = 0; } return line[idx++]; } public long nextLong() throws IOException, NumberFormatException { return Long.parseLong(nextToken()); } public int nextInt() throws NumberFormatException, IOException { return (int) nextLong(); } public double nextDouble() throws NumberFormatException, IOException { return Double.parseDouble(nextToken()); } }