#include<iostream>
#include<algorithm>
#include<stack>
#include<vector>
#include<set>
#include<string>
#include<cstdint>
#include<map>

using namespace std;
using ll = long long;

#include<bits/stdc++.h>

#line 1 "graph/flow/dinic.hpp"
/**
 * @brief Dinic(最大流)
 * @docs docs/dinic.md
 */
template< typename flow_t >
struct Dinic {
  const flow_t INF;

  struct edge {
    int to;
    flow_t cap;
    int rev;
    bool isrev;
    int idx;
  };

  vector< vector< edge > > graph;
  vector< int > min_cost, iter;

  explicit Dinic(int V) : INF(numeric_limits< flow_t >::max()), graph(V) {}

  void add_edge(int from, int to, flow_t cap, int idx = -1) {
    graph[from].emplace_back((edge) {to, cap, (int) graph[to].size(), false, idx});
    graph[to].emplace_back((edge) {from, 0, (int) graph[from].size() - 1, true, idx});
  }

  bool build_augment_path(int s, int t) {
    min_cost.assign(graph.size(), -1);
    queue< int > que;
    min_cost[s] = 0;
    que.push(s);
    while(!que.empty() && min_cost[t] == -1) {
      int p = que.front();
      que.pop();
      for(auto &e: graph[p]) {
        if(e.cap > 0 && min_cost[e.to] == -1) {
          min_cost[e.to] = min_cost[p] + 1;
          que.push(e.to);
        }
      }
    }
    return min_cost[t] != -1;
  }

  flow_t find_min_dist_augment_path(int idx, const int t, flow_t flow) {
    if(idx == t) return flow;
    for(int &i = iter[idx]; i < (int) graph[idx].size(); i++) {
      edge &e = graph[idx][i];
      if(e.cap > 0 && min_cost[idx] < min_cost[e.to]) {
        flow_t d = find_min_dist_augment_path(e.to, t, min(flow, e.cap));
        if(d > 0) {
          e.cap -= d;
          graph[e.to][e.rev].cap += d;
          return d;
        }
      }
    }
    return 0;
  }

  flow_t max_flow(int s, int t) {
    flow_t flow = 0;
    while(build_augment_path(s, t)) {
      iter.assign(graph.size(), 0);
      flow_t f;
      while((f = find_min_dist_augment_path(s, t, INF)) > 0) flow += f;
    }
    return flow;
  }

  void output() {
    for(int i = 0; i < graph.size(); i++) {
      for(auto &e: graph[i]) {
        if(e.isrev) continue;
        auto &rev_e = graph[e.to][e.rev];
        cout << i << "->" << e.to << " (flow: " << rev_e.cap << "/" << e.cap + rev_e.cap << ")" << endl;
      }
    }
  }

  vector< bool > min_cut(int s) {
    vector< bool > used(graph.size());
    queue< int > que;
    que.emplace(s);
    used[s] = true;
    while(not que.empty()) {
      int p = que.front();
      que.pop();
      for(auto &e: graph[p]) {
        if(e.cap > 0 and not used[e.to]) {
          used[e.to] = true;
          que.emplace(e.to);
        }
      }
    }
    return used;
  }
};

int main(){
    cin.tie(nullptr);
    ios::sync_with_stdio(false);

    int h,w;
    cin>>h>>w;
    vector<string> s(h);
    for(int i = 0;i<h;i++) cin>>s[i];
    Dinic<int> dinic(h*w+2);
    int ss = h * w;
    int t = ss + 1;
    int dx[] = {1,-1,0,0};
    int dy[] = {0,0,1,-1};

    int cnt = 0;
    for(int i = 0;i<h;i++){
        for(int j = 0;j<w;j++){
            if(s[i][j]=='h'){
                dinic.add_edge(i*w+j,t,1);
                continue;
            }
            if(s[i][j]=='r'){
                cnt++;
                dinic.add_edge(ss,i*w+j,1);
                for(int k = 0;k<4;k++){
                    int now = 1;
                    while(true){
                        int ni = i + now * dx[k];
                        int nj = j + now * dy[k];
                        if(ni<0||ni>=h||nj<0||nj>=w) break;
                        if(s[ni][nj]=='h'){
                            dinic.add_edge(i*w+j,ni*w+nj,1);
                            break;
                        }
                        now++;
                    }
                }
            }
        }
    }

    int ans = dinic.max_flow(ss,t);
    if(ans==cnt) cout<<"Yes\n";
    else cout<<"No\n";
}