#include <bits/stdc++.h>
using namespace std;

using Int = long long;
const char newl = '\n';

template<typename T1,typename T2> inline void chmin(T1 &a,T2 b){if(a>b) a=b;}
template<typename T1,typename T2> inline void chmax(T1 &a,T2 b){if(a<b) a=b;}
template<typename T> void drop(const T &x){cout<<x<<endl;exit(0);}
template<typename T=Int>
vector<T> read(size_t n){
  vector<T> ts(n);
  for(size_t i=0;i<n;i++) cin>>ts[i];
  return ts;
}


struct UnionFind{
  Int num;
  vector<Int> rs,ps;
  UnionFind(Int n):num(n),rs(n,1),ps(n,0){
    iota(ps.begin(),ps.end(),0);
  }
  Int find(Int x){
    return (x==ps[x]?x:ps[x]=find(ps[x]));
  }
  bool same(Int x,Int y){
    return find(x)==find(y);
  }
  void unite(Int x,Int y){
    x=find(x);y=find(y);
    if(x==y) return;
    if(rs[x]<rs[y]) swap(x,y);
    rs[x]+=rs[y];
    ps[y]=x;
    num--;
  }
  Int size(Int x){
    return rs[find(x)];
  }
  Int count() const{
    return num;
  }
};


template<typename T, T MOD = 1000000007>
struct Mint{
  inline static constexpr T mod = MOD;
  T v;
  Mint():v(0){}
  Mint(signed v):v(v){}
  Mint(long long t){v=t%MOD;if(v<0) v+=MOD;}

  Mint pow(long long k){
    Mint res(1),tmp(v);
    while(k){
      if(k&1) res*=tmp;
      tmp*=tmp;
      k>>=1;
    }
    return res;
  }

  static Mint add_identity(){return Mint(0);}
  static Mint mul_identity(){return Mint(1);}

  Mint inv(){return pow(MOD-2);}

  Mint& operator+=(Mint a){v+=a.v;if(v>=MOD)v-=MOD;return *this;}
  Mint& operator-=(Mint a){v+=MOD-a.v;if(v>=MOD)v-=MOD;return *this;}
  Mint& operator*=(Mint a){v=1LL*v*a.v%MOD;return *this;}
  Mint& operator/=(Mint a){return (*this)*=a.inv();}

  Mint operator+(Mint a) const{return Mint(v)+=a;}
  Mint operator-(Mint a) const{return Mint(v)-=a;}
  Mint operator*(Mint a) const{return Mint(v)*=a;}
  Mint operator/(Mint a) const{return Mint(v)/=a;}

  Mint operator+() const{return *this;}
  Mint operator-() const{return v?Mint(MOD-v):Mint(v);}

  bool operator==(const Mint a)const{return v==a.v;}
  bool operator!=(const Mint a)const{return v!=a.v;}

  static Mint comb(long long n,Int k){
    Mint num(1),dom(1);
    for(Int i=0;i<k;i++){
      num*=Mint(n-i);
      dom*=Mint(i+1);
    }
    return num/dom;
  }
};
template<typename T, T MOD>
ostream& operator<<(ostream &os,Mint<T, MOD> m){os<<m.v;return os;}

//INSERT ABOVE HERE
signed main(){
  cin.tie(0);
  ios::sync_with_stdio(0);

  Int h,w;
  cin>>h>>w;
  vector A(h,vector<Int>(w));
  for(Int i=0;i<h;i++)
    for(Int j=0;j<w;j++)
      cin>>A[i][j];

  using T = tuple<Int, Int, Int>;
  vector<T> vt;
  for(Int i=0;i<h;i++)
    for(Int j=0;j<w;j++)
      vt.emplace_back(A[i][j],i,j);
  sort(vt.rbegin(),vt.rend());

  using M = Mint<Int, 998244353>;
  M ans{0};
  UnionFind uf(h+w);
  for(auto[v,i,j]:vt){
    if(uf.same(i,h+j)) continue;
    uf.unite(i,h+j);
    ans+=M(v)*M(2).pow(uf.count()-1);
  }
  cout<<ans<<newl;
  return 0;
}