#include<iostream>
#include<vector>
#include<algorithm>
#include<tuple>
using namespace std;
using ll=long long;
#define rep(i,n) for(int i=0;i<n;i++)
#define rrep(i,n) for(int i=(n)-1;i>=0;i--)
#define all(v) v.begin(),v.end()
#define rall(v) v.rbegin(),v.rend()
template<class T> bool chmax(T &a, T b){if (a < b){a = b;return true;} else return false;}
template<class T> bool chmin(T &a, T b){if (a > b){a = b;return true;} else return false;}

struct UnionFind {
    vector<int> par, siz;
    UnionFind(int n) : par(n,-1), siz(n,1) {}
    int find(int x){
        if (par[x] == -1) return x;
        else{
            par[x] = find(par[x]);
            return par[x];
        }
    }
    bool same(int x, int y){
        return find(x) == find(y);
    }
    int size(int x){
        return siz[find(x)];
    }
    void merge(int x, int y){
        x = find(x);
        y = find(y);
        if (x == y) return;
        if (siz[x] < siz[y]) swap(x,y);
        siz[x] += siz[y];
        par[y] = x;
    }
};

const ll MOD=998244353;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int h,w;
    cin>>h>>w;
    vector<vector<ll>>A(h,vector<ll>(w));
    vector<tuple<ll,int,int>>V;
    rep(i,h)rep(j,w){
        cin>>A[i][j];
        V.push_back(make_tuple(A[i][j],i,j));
    }
    sort(rall(V));
    ll ans=0;
    vector<ll>P(h+w);
    P[0]=1;
    rep(i,h+w-1)P[i+1]=(2*P[i])%MOD;
    int x=h+w-2;
    UnionFind uf(h+w);
    for(auto[c,i,j]:V){
        if(x>=0&&(!uf.same(i,h+j))){
            uf.merge(i,h+j);
            ans+=c*P[x]%MOD;
            ans%=MOD;
            x--;
        }
    }
    cout<<ans<<"\n";
}