#include <bits/stdc++.h>
using namespace std;
const int N = 200;
char f[N][N];
char mb[N][N];
vector<int> gr[N];
int comp[N];
vector<int> strs[N];
vector<int> rows[N];
bool act[N];
void dfs(int v, int curcomp) {
  comp[v] = curcomp;
  for (int to : gr[v])
    if (!comp[to])
      dfs(to, curcomp);
    else if (comp[to] < curcomp) {
      printf("No");
      exit(0);
    }
}
int main() {
  int n, m;
  scanf("%d%d", &n, &m);
  for (int i = 0; i < n; ++i) scanf("%s", f[i]);
  for (int i = 0; i < n; ++i)
    for (int j = 0; j < m; ++j)
      if (f[i][j] == '#') {
        gr[i].push_back(n + j);
        gr[n + j].push_back(i);
        act[i] = act[n + j] = true;
      }
  int curcomp = 0;
  for (int i = 0; i < n + m; ++i)
    if (!comp[i] && act[i]) dfs(i, ++curcomp);
  for (int i = 0; i < n; ++i) rows[comp[i]].push_back(i);
  for (int i = 0; i < m; ++i) strs[comp[n + i]].push_back(i);
  for (int i = 0; i < n; ++i)
    for (int j = 0; j < m; ++j) mb[i][j] = '.';
  for (int i = 1; i <= curcomp; ++i)
    for (int row : rows[i])
      for (int str : strs[i]) mb[row][str] = '#';
  for (int i = 0; i < n; ++i)
    for (int j = 0; j < m; ++j)
      if (mb[i][j] != f[i][j]) {
        printf("No");
        return 0;
      }
  printf("Yes");
  return 0;
}
