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

#include <bits/stdc++.h>
int main() {
  int n, m;
  scanf("%d %d", &n, &m);
  char grid[n][m + 1];
  int yy[n], xx[m];
  std::vector<std::pair<int, int> > plist;
  std::map<int, bool> xmap, ymap;
  memset(grid, 0, sizeof(grid));
  memset(yy, 0xff, sizeof(yy));
  memset(xx, 0xff, sizeof(xx));
  for (int i = 0; i < n; i++) {
    scanf("%s", grid[i]);
    for (int j = 0; j < m; j++) {
      if (grid[i][j] == '#') plist.push_back(std::pair<int, int>(i, j));
    }
  }
  bool flag = true;
  for (int i = 0; flag && i < plist.size(); i++) {
    if (plist[i].first == -1) continue;
    int kill_dot = 1;
    xmap.clear();
    ymap.clear();
    xmap[plist[i].first] = true;
    ymap[plist[i].second] = true;
    xx[plist[i].first] = i;
    yy[plist[i].second] = i;
    printf("Kill (%d,%d), ", plist[i].first, plist[i].second);
    for (int j = i + 1; j < plist.size(); j++) {
      if (plist[j].first == -1) continue;
      printf("Check (%d,%d)\n", plist[j].first, plist[j].second);
      if (plist[i].second == plist[j].second || yy[plist[j].second] == i) {
        if (yy[plist[j].second] != -1 && yy[plist[j].second] != i) {
          flag = false;
          break;
        } else {
          xmap[plist[j].first] = true;
          ymap[plist[j].second] = true;
          xx[plist[j].first] = i;
          yy[plist[j].second] = i;
          printf("Kill (%d,%d), ", plist[j].first, plist[j].second);
          plist[j].first == -1;
          kill_dot++;
          continue;
        }
      }
      if (plist[i].first == plist[j].first || xx[plist[j].first] == i) {
        if (xx[plist[j].first] != -1 && xx[plist[j].first] != i) {
          flag = false;
          break;
        } else {
          xmap[plist[j].first] = true;
          ymap[plist[j].second] = true;
          xx[plist[j].first] = i;
          yy[plist[j].second] = i;
          printf("Kill (%d,%d), ", plist[j].first, plist[j].second);
          plist[j].first == -1;
          kill_dot++;
          continue;
        }
      }
    }
    if (kill_dot != xmap.size() * ymap.size()) flag = false;
    printf("(%d,%d) kills %d * %d but %d\n", plist[i].first, plist[i].second,
           xmap.size(), ymap.size(), kill_dot);
  }
  printf(flag ? "Yes\n" : "No\n");
  return 0;
}
