9 5
.....
#....
..#..
.....
.#..#
...#.
.#...
....#
.....
 4 10
..#......#
.....##...
#.........
.#.......#
 50 2
..
..
#.
..
.#
..
..
..
.#
..
..
.#
##
..
..
..
.#
..
..
.#
..
..
.#
..
..
.#
..
.#
..
.#
..
.#
.#
.#
..
..
..
.#
.#
.#
..
..
.#
.#
..
..
..
..
..
..
 2 50
...#.##.###...#.#..##....##..........#.#..#.#####.
...#.##.###...#.#..##....##..........#.#..#.#####.
 1 1
#
 3 3
.##
#.#
##.
 50 8
.....#..
........
........
.....#..
.....#..
........
........
........
........
...#....
...#....
........
...#....
#.#.#...
...#....
...#....
........
...#....
...#....
...#....
........
#.#.#...
.....#..
........
#.#.#...
#.#.#...
#.#.#...
...#....
........
........
........
#.#.#...
........
.....#..
........
........
........
........
........
........
.....#..
........
........
........
.....#..
#.#.#...
...#....
........
........
........
 1 1
.
 25 16
.............#..
.............#..
.......#...#....
............#...
.....#..........
.....#..........
#...............
................
........#.......
................
................
.#..............
#...............
.....#..........
.#..............
............#...
................
................
................
........#.......
..#.............
..........#.....
.......#...#....
.............#..
..........#.....
 25 16
..............#.
................
...#...#........
........#.#.....
..............##
..............#.
.......#........
......#.........
............#...
.........#.....#
..............#.
.......#........
#...........#...
...#.#..........
.#..............
................
......#.....#...
.......#........
........#.....#.
................
......#.........
..#.............
................
...#.#..........
.#..............
 10 15
.......#.......
.....#.........
....#..........
....#..........
.....#.........
.....#.........
#.............#
...#..#........
...............
.............#.
 4 10
###..#..##
...##..#..
.##..#..#.
.........#
 2 5
.####
#..##
 5 2
##
##
..
##
..
 2 2
##
#.
 50 1
.
.
#
.
#
.
#
.
.
#
#
#
.
#
#
#
#
.
.
.
.
.
.
.
.
.
#
#
#
#
.
.
.
.
.
#
.
.
.
#
#
.
.
#
#
.
.
#
#
.
 5 2
#.
##
##
#.
..
 2 3
#.#
###
 2 1
.
#
 2 3
#.#
##.
 10 10
..........
..........
..........
..........
.#.......#
#.........
......#...
..........
..........
#.....#...
 4 4
###.
##.#
#.##
.###

No
 No
 No
 Yes
 Yes
 No
 Yes
 Yes
 Yes
 No
 Yes
 No
 No
 Yes
 No
 Yes
 No
 No
 Yes
 No
 No
 No

import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.StringTokenizer;
import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author Liavontsi Brechka
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        TaskB solver = new TaskB();
        solver.solve(1, in, out);
        out.close();
    }

    static
    @SuppressWarnings("Duplicates")
    class TaskB {
        int n;
        int m;
        boolean[][] isDark;
        int[][][] visit;
        boolean isPossible;
        boolean[] isUsedRow;
        boolean[] isUsedColumn;

        public void solve(int testNumber, InputReader in, PrintWriter out) {
            n = in.nextInt();
            m = in.nextInt();
            isDark = new boolean[n][m];
            visit = new int[n][m][2];
            isPossible = true;
            isUsedRow = new boolean[n];
            isUsedColumn = new boolean[m];

            String next;
            for (int i = 0; i < n; i++) {
                next = in.next();
                for (int j = 0; j < m; j++) {
                    isDark[i][j] = next.charAt(j) == '#';
                }
            }

            for (int i = 0; i < n && isPossible; i++) {
                if (!isUsedRow[i]) {
                    isUsedRow[i] = true;
                    dfs(i, 0, true, i + 1);
                }
            }

            for (int i = 0; i < m && isPossible; i++) {
                if (!isUsedColumn[i]) {
                    isUsedColumn[i] = true;
                    dfs(0, i, false, i + 1);
                }
            }

            out.print(isPossible ? "Yes" : "No");
        }

        private void dfs(int i, int j, boolean isHoriz, int number) {
            if (!isPossible || i < 0 || j < 0 || i >= n || j >= m) return;
            if (visit[i][j][0] == number || visit[i][j][1] == number) {
                if (!isDark[i][j] && visit[i][j][isHoriz ? 1 : 0] == number) isPossible = false;
                return;
            }

            visit[i][j][isHoriz ? 0 : 1] = number;

            if (isDark[i][j]) {
                if (isHoriz) {
                    isUsedColumn[j] = true;
                    dfs(i - 1, j, false, number);
                    dfs(i + 1, j, false, number);
                } else {
                    isUsedRow[i] = true;
                    dfs(i, j - 1, true, number);
                    dfs(i, j + 1, true, number);
                }
            } else {
                if (isHoriz) {
                    dfs(i, j - 1, true, number);
                    dfs(i, j + 1, true, number);
                } else {
                    dfs(i - 1, j, false, number);
                    dfs(i + 1, j, false, number);
                }
            }
        }

    }

    static class InputReader {
        private final BufferedReader reader;
        private StringTokenizer tokenizer;

        public InputReader(InputStream in) {
            reader = new BufferedReader(new InputStreamReader(in));
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

        public String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                tokenizer = new StringTokenizer(readLine());
            }
            return tokenizer.nextToken();
        }

        public String readLine() {
            String line;
            try {
                line = reader.readLine();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
            return line;
        }

    }
}

