#include <bits/stdc++.h>
#define rep(i,n) for (int i=0; i<(int)(n); i++)
#define REP(i,m,n) for(ll i=(ll)(m);i<(ll)(n);i++)
using namespace std;
using ll = long long;
using P = pair<int, int>;

int main() {
  // Grid Repainting 2
  int h, w; cin >> h >> w;
  vector<string> s(h);
  rep(i,h) cin >> s.at(i);

  vector<int> di = {1, 0, -1, 0};
  vector<int> dj = {0, 1, 0, -1};

  rep(i,h) {
    rep(j,w) {
      if (s.at(i).at(j) == '#') {
        int cnt = 0;
        rep(k,4) {
          int ni = i + di[k];
          int nj = j + dj[k];
          if (0 <= ni && ni < h && 0 <= nj && nj < w) {
            if (s.at(ni).at(nj) == '.') cnt++;
          }
        }
        if (cnt == 4) {
          cout << "No" << endl;
          return 0;
        }
      }
    }
  }
  cout << "Yes" << endl;
  return 0;
}
#include <bits/stdc++.h>
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define rep(i,n) for (int i=0;i<(int)(n);i++)
#define codefor int test;scanf("%d",&test);while(test--)
#define yn(ans) if(ans)printf("Yes\n");else printf("No\n")
#define YN(ans) if(ans)printf("YES\n");else printf("NO\n")
#define umap unordered_map
#define uset unordered_set
using namespace std;
using ll = long long;
const int MOD=1000000007;
//入力系
void scan(int& a){scanf("%d",&a);}
void scan(long long& a){scanf("%lld",&a);}
template<class T> void scan(T& a){cin>>a;}
template<class T> void scan(vector<T>& vec){for(auto&& it:vec)scan(it);}
void in(){}
template <class Head, class... Tail> void in(Head& head, Tail&... tail){scan(head);in(tail...);}
//出力系
void print(const int& a){printf("%d",a);}
void print(const long long& a){printf("%lld",a);}
void print(const double& a){printf("%.15lf",a);}
template<class T> void print(const T& a){cout<<a;}
template<class T> void print(const vector<T>& vec){if(vec.empty())return;print(vec[0]);for(auto it=vec.begin();++it!= vec.end();){putchar(' ');print(*it);}}
void out(){putchar('\n');}
template<class T> void out(const T& t){print(t);putchar('\n');}
template <class Head, class... Tail> void out(const Head& head,const Tail&... tail){print(head);putchar(' ');out(tail...);}
//デバッグ系
template<class T> void dprint(const T& a){cerr<<a;}
template<class T> void dprint(const vector<T>& vec){if(vec.empty())return;cerr<<vec[0];for(auto it=vec.begin();++it!= vec.end();){cerr<<" "<<*it;}}
void debug(){cerr<<endl;}
template<class T> void debug(const T& t){dprint(t);cerr<<endl;}
template <class Head, class... Tail> void debug(const Head& head, const Tail&... tail){dprint(head);cerr<<" ";debug(tail...);}

int main(){
    string s;
    cin>>s;
    if(s=="zyxwvutsrqponmlkjihgfedcba"){
        out(-1);
        return 0;
    }
    if(s.length()<26){
    cout<<s;
    char c='a';
    rep(i,26){
        if(count(all(s),c)==0){
            cout<<c<<endl;
            return 0;
        }
        c++;
    }
    }else if(s.length()==26){
        int n=25,d=0;
        while(1){
            s[n]++;
            if(s[n]>'z'){
                s[n-1]++;
                s.erase(s.begin()+n);
                n--;
            }
            if(s[n]>='a'&&s[n]<='z'&&count(all(s),s[n])==1)break;
        }
        cout<<s<<endl;
    }
}